485BPOS

As filed with the U.S. Securities and Exchange Commission on February 13, 2013

Securities Act File No. 33-47875

Investment Company Act File No. 811-06669

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT

UNDER
THE SECURITIES ACT OF 1933	x
Pre-Effective Amendment No.	¨
Post-Effective Amendment No. 29	x
and/or
REGISTRATION STATEMENT
UNDER
THE INVESTMENT COMPANY ACT OF 1940	x
Amendment No. 30

(Check appropriate box or boxes)

BlackRock Capital Appreciation Fund, Inc.

(Exact Name of Registrant as Specified in Charter)

100 Bellevue Parkway

Wilmington, Delaware 19809

(Address of Principal Executive Office)

Registrant’s Telephone Number, including Area Code (800) 441-7762

John M. Perlowski

BlackRock Capital Appreciation Fund, Inc.

55 East 52^nd Street, New York, New York 10055

(Name and Address of Agent for Service)

Copies to:

Counsel for the Fund: Margery K. Neale, Esq. Willkie Farr & Gallagher LLP 787 Seventh Avenue New York, New York 10019-6099 Benjamin Archibald, Esq. BlackRock Advisors, LLC 55 East 52^nd Street New York, New York 10055

Continuous

(Approximate Date of Proposed Offering)

It is proposed that this filing will become effective:

x immediately upon filing pursuant to paragraph (b)

¨ on (date) pursuant to paragraph (b)

¨ 60 days after filing pursuant to paragraph (a)(1)

¨ on (date) pursuant to paragraph (a)(1)

¨ 75 days after filing pursuant to paragraph (a)(2)

¨ on (date) pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box:

¨ This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

Title of Securities Being Registered: Shares of Common Stock, par value, $0.10 per share.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all the requirements for the effectiveness of this Registration Statement under Rule 485(b) under the Securities Act and it has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, and the State of New York on February 13, 2013.

	BlackRock Capital Appreciation Fund, Inc.
	(Registrant)
By:	/s/ JOHN M. PERLOWSKI
	(John M. Perlowski,
	President and Chief Executive Officer)

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment to the Registration Statement has been signed below by the following persons in the capacities and on the dates indicated:

Signature	Title	Date
/s/ JOHN M. PERLOWSKI	President and Chief Executive Officer	February 13, 2013
John M. Perlowski	(Principal Executive Officer)
/s/ NEAL J. ANDREWS	Chief Financial Officer (Principal	February 13, 2013
Neal J. Andrews	Financial and Accounting Officer)
JAMES H. BODURTHA*	Director
(James H. Bodurtha)
BRUCE R. BOND*	Director
(Bruce R. Bond)
DONALD W. BURTON*	Director
(Donald W. Burton)
STUART E. EIZENSTAT*	Director
(Stuart E. Eizenstat)
KENNETH A. FROOT*	Director
(Kenneth A. Froot)
ROBERT M. HERNANDEZ*	Director
(Robert M. Hernandez)

JOHN F. O’BRIEN*		Director
(John F. O’Brien)
ROBERTA COOPER RAMO*		Director
(Roberta Cooper Ramo)
DAVID H. WALSH*		Director
(David H. Walsh)
FRED G. WEISS*		Director
(Fred G. Weiss)
PAUL L. AUDET*		Director
(Paul L. Audet)
LAURENCE D. FINK*		Director
(Laurence D. Fink)
HENRY GABBAY*		Director
(Henry Gabbay)
*By:	/s/ BEN ARCHIBALD		February 13, 2013
	Ben Archibald (Attorney-in-Fact)

EXHIBIT INDEX

Index No.	Description of Exhibit
EX-101.INS	XBRL Instance Document
EX-101.SCH	XBRL Taxonomy Extension Schema Document
EX-101.CAL	XBRL Taxonomy Extension Calculation Linkbase
EX-101.DEF	XBRL Taxonomy Extension Definition Linkbase
EX-101.LAB	XBRL Taxonomy Extension Labels Linkbase
EX-101.PRE	XBRL Taxonomy Extension Presentation Linkbase

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	BlackRock Capital Appreciation Fund, Inc.
Prospectus Date	rr_ProspectusDate	Jan. 28, 2013
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC.
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Overview Key Facts about BlackRock Capital Appreciation Fund, Inc.
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The investment objective of the BlackRock Capital Appreciation Fund, Inc. (the “Fund”) is to seek long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the BlackRock-advised fund complex. More information about these and other discounts is available from your financial professional and in the “Details about the Share Classes” section on page 18 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-58 of the Fund’s statement of additional information.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	February 1, 2023
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover:
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 77% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	77.00%
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	A contingent deferred sales charge (“CDSC”) of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the BlackRock-advised fund complex.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	25,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example:
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example, No Redemption, By Year, Caption [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	You would pay the following expenses if you did not redeem your shares:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies of the Fund
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will seek to achieve its investment objective by investing primarily in a diversified portfolio consisting primarily of common stock of U.S. companies that Fund management believes have exhibited above-average growth rates in earnings over the long term. In other words, Fund management tries to choose investments that will increase in value over the long term. The Fund will generally invest at least 65% of its total assets in the following equity securities: Common stock; Convertible preferred stock; Securities convertible into common stock; and Rights to subscribe to common stock. Of these securities the Fund generally seeks to invest primarily in common stock. The Fund may invest in companies of any size but emphasizes investments in companies that have medium to large stock market capitalizations (currently, approximately $2 billion or more). Convertible securities generally are debt securities or preferred stock that may be converted into common stock. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock). A convertible’s value usually reflects both the stream of current income payments and the market value of the underlying common stock. The Fund may purchase securities pursuant to the exercise of subscription rights, which allow an issuer’s existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.
Risk [Heading]	rr_RiskHeading	Principal Risks of Investing in the Fund
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund. Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock. Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles. Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money. Mid Cap Securities Risk — The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. Effective June 28, 2010, the Fund reorganized with the BlackRock Capital Appreciation Portfolio (the “Predecessor Fund”), a series of BlackRock FundsSM (the “Reorganization”), and the Predecessor Fund’s performance and financial history has been adopted by the Fund from the date of the Reorganization. The performance of Investor A, Investor B and Investor C Shares of the Fund is based off of the performance of those same share classes of the Predecessor Fund, with no adjustments. The performance of Class R and Institutional Shares of the Fund, is based off of the performance of Institutional Shares of the Predecessor Fund, adjusted to reflect the distribution and service (12b-1 fees) and other fees, if any, that are applicable to such class of shares. On January 31, 2005, the Predecessor Fund reorganized with the State Street Research Legacy Fund (the “SSR Fund”), which had investment goals and strategies substantially similar to the Fund. For periods prior to January 31, 2005, the chart and table show performance information for the SSR Fund. The table compares the Fund’s performance to that of the Russell 1000® Growth Index and the S&P 500® Index, which are relevant to the Fund because they have characteristics similar to the Fund’s investment strategy. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at (800) 882-0052.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	(800) 882-0052
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	http://www.blackrock.com/funds
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As with all such investments, past performance (before and after taxes) is not an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Investor A Shares ANNUAL TOTAL RETURNS BlackRock Capital Appreciation Fund As of 12/31
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	During the ten-year period shown in the bar chart, the highest return for a quarter was 16.61% (quarter ended September 30, 2009) and the lowest return for a quarter was –22.93% (quarter ended December 31, 2008).
Performance Table Heading	rr_PerformanceTableHeading	As of 12/31/12 Average Annual Total Returns
Performance Table Does Reflect Sales Loads	rr_PerformanceTableDoesReflectSalesLoads	However, the table includes all applicable fees and sales charges.
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C, Institutional and Class R Shares will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C, Institutional and Class R Shares will vary.
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.25%
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none	[1]
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.23%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.09%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.09%
1 Year	rr_ExpenseExampleYear01	630
3 Years	rr_ExpenseExampleYear03	853
5 Years	rr_ExpenseExampleYear05	1,094
10 Years	rr_ExpenseExampleYear10	1,784
2003	rr_AnnualReturn2003	28.90%
2004	rr_AnnualReturn2004	9.68%
2005	rr_AnnualReturn2005	6.47%
2006	rr_AnnualReturn2006	3.66%
2007	rr_AnnualReturn2007	18.25%
2008	rr_AnnualReturn2008	(36.56%)
2009	rr_AnnualReturn2009	36.18%
2010	rr_AnnualReturn2010	19.13%
2011	rr_AnnualReturn2011	(9.14%)
2012	rr_AnnualReturn2012	13.93%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	highest return
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	16.61%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	lowest return
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(22.93%)
1 Year	rr_AverageAnnualReturnYear01	7.93%
5 Years	rr_AverageAnnualReturnYear05	0.19%
10 Years	rr_AverageAnnualReturnYear10	6.42%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Investor B Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	4.50%	[2]
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.43%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.04%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	2.04%
1 Year	rr_ExpenseExampleYear01	657
3 Years	rr_ExpenseExampleYear03	990
5 Years	rr_ExpenseExampleYear05	1,298
10 Years	rr_ExpenseExampleYear10	2,124
1 Year	rr_ExpenseExampleNoRedemptionYear01	207
3 Years	rr_ExpenseExampleNoRedemptionYear03	640
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,098
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,124
1 Year	rr_AverageAnnualReturnYear01	8.23%
5 Years	rr_AverageAnnualReturnYear05	(0.01%)
10 Years	rr_AverageAnnualReturnYear10	6.32%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Investor C Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%	[3]
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.31%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.92%	[4]
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.92%	[4]
1 Year	rr_ExpenseExampleYear01	295
3 Years	rr_ExpenseExampleYear03	603
5 Years	rr_ExpenseExampleYear05	1,037
10 Years	rr_ExpenseExampleYear10	2,243
1 Year	rr_ExpenseExampleNoRedemptionYear01	195
3 Years	rr_ExpenseExampleNoRedemptionYear03	603
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,037
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,243
1 Year	rr_AverageAnnualReturnYear01	11.93%
5 Years	rr_AverageAnnualReturnYear05	0.52%
10 Years	rr_AverageAnnualReturnYear10	6.22%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Institutional Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.23%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.84%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	0.84%
1 Year	rr_ExpenseExampleYear01	86
3 Years	rr_ExpenseExampleYear03	268
5 Years	rr_ExpenseExampleYear05	466
10 Years	rr_ExpenseExampleYear10	1,037
1 Year	rr_AverageAnnualReturnYear01	14.15%
5 Years	rr_AverageAnnualReturnYear05	1.59%
10 Years	rr_AverageAnnualReturnYear10	7.25%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Class R Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other Expenses	rr_OtherExpensesOverAssets	0.28%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.39%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.39%
1 Year	rr_ExpenseExampleYear01	142
3 Years	rr_ExpenseExampleYear03	440
5 Years	rr_ExpenseExampleYear05	761
10 Years	rr_ExpenseExampleYear10	1,669
1 Year	rr_AverageAnnualReturnYear01	13.53%
5 Years	rr_AverageAnnualReturnYear05	0.93%
10 Years	rr_AverageAnnualReturnYear10	6.54%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Return After Taxes on Distributions | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	7.90%
5 Years	rr_AverageAnnualReturnYear05	0.18%
10 Years	rr_AverageAnnualReturnYear10	6.42%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Return After Taxes on Distributions and Sale of Shares | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	5.20%
5 Years	rr_AverageAnnualReturnYear05	0.16%
10 Years	rr_AverageAnnualReturnYear10	5.66%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Russell 1000® Growth Index (Reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.26%
5 Years	rr_AverageAnnualReturnYear05	3.12%
10 Years	rr_AverageAnnualReturnYear10	7.52%
Investor, Institutional and R Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Standard & Poor's (S&P) 500® Index (Reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	16.00%
5 Years	rr_AverageAnnualReturnYear05	1.66%
10 Years	rr_AverageAnnualReturnYear10	7.10%

[1] A contingent deferred sales charge ("CDSC") of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.

[2] The CDSC is 4.50% if shares are redeemed in less than one year. The CDSC for Investor B Shares decreases for redemptions made in subsequent years. After six years there is no CDSC on Investor B Shares. (See the section "Details about the Share Classes - Investor B Shares" in the Fund's prospectus for the complete schedule of CDSCs.)

[3] There is no CDSC on Investor C Shares after one year.

[4] As described in the "Management of the Fund" section of the Fund's prospectus on page 33, BlackRock has contractually agreed to waive fees and/or reimburse expenses in order to limit the Fund's Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) for Investor C Shares to 1.94% of average daily net assets until February 1, 2023. On February 1 of each year, the waiver agreement will renew automatically for an additional one year so that the agreement will have a perpetual ten year term. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested Directors of the Fund or by a vote of a majority of the outstanding voting securities of the Fund.

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Investor, Institutional and R Shares

Fund Overview

Key Facts about BlackRock Capital Appreciation Fund, Inc.

Investment Objective

The investment objective of the BlackRock Capital Appreciation Fund, Inc. (the “Fund”) is to seek long-term growth of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the BlackRock-advised fund complex. More information about these and other discounts is available from your financial professional and in the “Details about the Share Classes” section on page 18 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-58 of the Fund’s statement of additional information.

Shareholder Fees
(fees paid directly from your investment)

Shareholder Fees Investor, Institutional and R Shares BLACKROCK CAPITAL APPRECIATION FUND, INC.	Investor A Shares		Investor B Shares		Investor C Shares		Institutional Shares	Class R Shares
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	5.25%		none		none		none	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	none	[1]	4.50%	[2]	1.00%	[3]	none	none

Annual Fund Operating Expenses
(expenses that you pay each year as a
percentage of the value of your investment)

Annual Fund Operating Expenses Investor, Institutional and R Shares BLACKROCK CAPITAL APPRECIATION FUND, INC.	Investor A Shares	Investor B Shares	Investor C Shares		Institutional Shares	Class R Shares
Management Fee	0.61%	0.61%	0.61%		0.61%	0.61%
Distribution and/or Service (12b-1) Fees	0.25%	1.00%	1.00%		none	0.50%
Other Expenses	0.23%	0.43%	0.31%		0.23%	0.28%
Total Annual Fund Operating Expenses	1.09%	2.04%	1.92%	[1]	0.84%	1.39%
Fee Waivers and/or Expense Reimbursements
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	1.09%	2.04%	1.92%	[1]	0.84%	1.39%

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example Investor, Institutional and R Shares BLACKROCK CAPITAL APPRECIATION FUND, INC. (USD $)	1 Year	3 Years	5 Years	10 Years
Investor A Shares	630	853	1,094	1,784
Investor B Shares	657	990	1,298	2,124
Investor C Shares	295	603	1,037	2,243
Institutional Shares	86	268	466	1,037
Class R Shares	142	440	761	1,669

You would pay the following expenses if you did not redeem your shares:

Expense Example, No Redemption Investor, Institutional and R Shares BLACKROCK CAPITAL APPRECIATION FUND, INC. (USD $)	1 Year	3 Years	5 Years	10 Years
Investor B Shares	207	640	1,098	2,124
Investor C Shares	195	603	1,037	2,243

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 77% of the average value of its portfolio.

Principal Investment Strategies of the Fund

The Fund will seek to achieve its investment objective by investing primarily in a diversified portfolio consisting primarily of common stock of U.S. companies that Fund management believes have exhibited above-average growth rates in earnings over the long term. In other words, Fund management tries to choose investments that will increase in value over the long term.

The Fund will generally invest at least 65% of its total assets in the following equity securities:

• Common stock;

• Convertible preferred stock;

• Securities convertible into common stock; and

• Rights to subscribe to common stock.

Of these securities the Fund generally seeks to invest primarily in common stock.

The Fund may invest in companies of any size but emphasizes investments in companies that have medium to large stock market capitalizations (currently, approximately $2 billion or more).

Convertible securities generally are debt securities or preferred stock that may be converted into common stock. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock). A convertible’s value usually reflects both the stream of current income payments and the market value of the underlying common stock. The Fund may purchase securities pursuant to the exercise of subscription rights, which allow an issuer’s existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.

Principal Risks of Investing in the Fund

Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund.

• Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock.

• Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions.

• Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.

• Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.

• Mid Cap Securities Risk — The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.

Performance Information

The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. Effective June 28, 2010, the Fund reorganized with the BlackRock Capital Appreciation Portfolio (the “Predecessor Fund”), a series of BlackRock Funds^SM (the “Reorganization”), and the Predecessor Fund’s performance and financial history has been adopted by the Fund from the date of the Reorganization. The performance of Investor A, Investor B and Investor C Shares of the Fund is based off of the performance of those same share classes of the Predecessor Fund, with no adjustments. The performance of Class R and Institutional Shares of the Fund, is based off of the performance of Institutional Shares of the Predecessor Fund, adjusted to reflect the distribution and service (12b-1 fees) and other fees, if any, that are applicable to such class of shares. On January 31, 2005, the Predecessor Fund reorganized with the State Street Research Legacy Fund (the “SSR Fund”), which had investment goals and strategies substantially similar to the Fund. For periods prior to January 31, 2005, the chart and table show performance information for the SSR Fund. The table compares the Fund’s performance to that of the Russell 1000^® Growth Index and the S&P 500^® Index, which are relevant to the Fund because they have characteristics similar to the Fund’s investment strategy. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at (800) 882-0052.

Investor A Shares
ANNUAL TOTAL RETURNS
BlackRock Capital Appreciation Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 16.61% (quarter ended September 30, 2009) and the lowest return for a quarter was –22.93% (quarter ended December 31, 2008).

As of 12/31/12
Average Annual Total Returns

Average Annual Total Returns Investor, Institutional and R Shares BLACKROCK CAPITAL APPRECIATION FUND, INC.	1 Year	5 Years	10 Years
Investor A	7.93%	0.19%	6.42%
Investor A Return After Taxes on Distributions	7.90%	0.18%	6.42%
Investor A Return After Taxes on Distributions and Sale of Shares	5.20%	0.16%	5.66%
Investor B	8.23%	(0.01%)	6.32%
Investor C	11.93%	0.52%	6.22%
Institutional	14.15%	1.59%	7.25%
Class R	13.53%	0.93%	6.54%
Russell 1000® Growth Index (Reflects no deduction for fees, expenses or taxes)	15.26%	3.12%	7.52%
Standard & Poor's (S&P) 500® Index (Reflects no deduction for fees, expenses or taxes)	16.00%	1.66%	7.10%

After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C, Institutional and Class R Shares will vary.

[1] A contingent deferred sales charge ("CDSC") of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.

[2] The CDSC is 4.50% if shares are redeemed in less than one year. The CDSC for Investor B Shares decreases for redemptions made in subsequent years. After six years there is no CDSC on Investor B Shares. (See the section "Details about the Share Classes - Investor B Shares" in the Fund's prospectus for the complete schedule of CDSCs.)

[3] There is no CDSC on Investor C Shares after one year.

[1] As described in the "Management of the Fund" section of the Fund's prospectus on page 33, BlackRock has contractually agreed to waive fees and/or reimburse expenses in order to limit the Fund's Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) for Investor C Shares to 1.94% of average daily net assets until February 1, 2023. On February 1 of each year, the waiver agreement will renew automatically for an additional one year so that the agreement will have a perpetual ten year term. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested Directors of the Fund or by a vote of a majority of the outstanding voting securities of the Fund.

XML

Document and Entity Information	12 Months Ended
	Jan. 28, 2013
Risk/Return:
Document Type	485BPOS
Document Period End Date	Sep. 30, 2012
Registrant Name	BlackRock Capital Appreciation Fund, Inc.
Central Index Key	0000887509
Amendment Flag	false
Document Creation Date	Jan. 28, 2013
Document Effective Date	Jan. 28, 2013
Prospectus Date	Jan. 28, 2013

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	BlackRock Capital Appreciation Fund, Inc.
Prospectus Date	rr_ProspectusDate	Jan. 28, 2013
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC.
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Overview Key Facts about BlackRock Capital Appreciation Fund, Inc.
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The investment objective of the BlackRock Capital Appreciation Fund, Inc. (the “Fund”) is to seek long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold BlackRock Shares of the Fund.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	February 1, 2023
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover:
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 77% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	77.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	Example:
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies of the Fund
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will seek to achieve its investment objective by investing primarily in a diversified portfolio consisting primarily of common stock of U.S. companies that Fund management believes have exhibited above-average growth rates in earnings over the long term. In other words, Fund management tries to choose investments that will increase in value over the long term. The Fund will generally invest at least 65% of its total assets in the following equity securities: Common stock; Convertible preferred stock; Securities convertible into common stock; and Rights to subscribe to common stock. Of these securities the Fund generally seeks to invest primarily in common stock. The Fund may invest in companies of any size but emphasizes investments in companies that have medium to large stock market capitalizations (currently, approximately $2 billion or more). Convertible securities generally are debt securities or preferred stock that may be converted into common stock. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock). A convertible’s value usually reflects both the stream of current income payments and the market value of the underlying common stock. The Fund may purchase securities pursuant to the exercise of subscription rights, which allow an issuer’s existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.
Risk [Heading]	rr_RiskHeading	Principal Risks of Investing in the Fund
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund. Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock. Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles. Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money. Mid Cap Securities Risk — The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. Effective June 28, 2010, the Fund reorganized with the BlackRock Capital Appreciation Portfolio (the “Predecessor Fund”), a series of BlackRock FundsSM (the “Reorganization”), and the Predecessor Fund’s performance and financial history has been adopted by the Fund from the date of the Reorganization. The performance of BlackRock Shares of the Fund is based off of the performance of Institutional Shares of the Predecessor Fund, with no adjustments. On January 31, 2005, the Predecessor Fund reorganized with the State Street Research Legacy Fund (the “SSR Fund”), which had investment goals and strategies substantially similar to the Fund. For periods prior to January 31, 2005, the chart and table show performance information for the SSR Fund. The table compares the Fund’s performance to that of the Russell 1000® Growth Index and the S&P 500® Index, which are relevant to the Fund because they have characteristics similar to the Fund’s investment strategy. As with all such investments, past performance (before and after taxes) is not an indication of future results. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at (800) 882-0052.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The information shows you how the Fund's performance has varied year by year and provides some indication of the risks of investing in the Fund.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	(800) 882-0052
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	http://www.blackrock.com/funds
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As with all such investments, past performance (before and after taxes) is not an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	BlackRock Shares ANNUAL TOTAL RETURNS BlackRock Capital Appreciation Fund As of 12/31
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	During the ten-year period shown in the bar chart, the highest return for a quarter was 16.64% (quarter ended September 30, 2009) and the lowest return for a quarter was –22.85% (quarter ended December 31, 2008).
Performance Table Heading	rr_PerformanceTableHeading	As of 12/31/12 Average Annual Total Returns
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | BlackRock Shares
Risk/Return:	rr_RiskReturnAbstract
Management Fee	rr_ManagementFeesOverAssets	0.61%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.16%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.77%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.05%)	[1]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	0.72%	[1]
1 Year	rr_ExpenseExampleYear01	74
3 Years	rr_ExpenseExampleYear03	230
5 Years	rr_ExpenseExampleYear05	401
10 Years	rr_ExpenseExampleYear10	894
2003	rr_AnnualReturn2003	29.26%
2004	rr_AnnualReturn2004	10.02%
2005	rr_AnnualReturn2005	6.74%
2006	rr_AnnualReturn2006	4.10%
2007	rr_AnnualReturn2007	18.84%
2008	rr_AnnualReturn2008	(36.21%)
2009	rr_AnnualReturn2009	36.87%
2010	rr_AnnualReturn2010	19.67%
2011	rr_AnnualReturn2011	(8.78%)
2012	rr_AnnualReturn2012	14.29%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	highest return
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	16.64%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	lowest return
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(22.85%)
1 Year	rr_AverageAnnualReturnYear01	14.29%
5 Years	rr_AverageAnnualReturnYear05	1.72%
10 Years	rr_AverageAnnualReturnYear10	7.42%
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Return After Taxes on Distributions | BlackRock Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	14.17%
5 Years	rr_AverageAnnualReturnYear05	1.69%
10 Years	rr_AverageAnnualReturnYear10	7.40%
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Return After Taxes on Distributions and Sale of Shares | BlackRock Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	9.46%
5 Years	rr_AverageAnnualReturnYear05	1.47%
10 Years	rr_AverageAnnualReturnYear10	6.56%
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Russell 1000® Growth Index (Reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.26%
5 Years	rr_AverageAnnualReturnYear05	3.12%
10 Years	rr_AverageAnnualReturnYear10	7.52%
BlackRock Shares | BLACKROCK CAPITAL APPRECIATION FUND, INC. | Standard & Poor's (S&P) 500® Index (Reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	16.00%
5 Years	rr_AverageAnnualReturnYear05	1.66%
10 Years	rr_AverageAnnualReturnYear10	7.10%

[1] As described in the "Management of the Fund" section of the Fund's prospectus on page 19, BlackRock has contractually agreed to waive fees and/or reimburse expenses in order to limit the Fund's Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) for BlackRock Shares to 0.72% of average daily net assets until February 1, 2023. On February 1 of each year, the waiver agreement will renew automatically for an additional one year so that the agreement will have a perpetual ten year term. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested Directors of the Fund or by a vote of a majority of the outstanding voting securities of the Fund.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	BlackRock Capital Appreciation Fund, Inc.
Prospectus Date	rr_ProspectusDate	Jan. 28, 2013
Document Creation Date	dei_DocumentCreationDate	Jan. 28, 2013

XML

BlackRock Shares

Fund Overview

Key Facts about BlackRock Capital Appreciation Fund, Inc.

Investment Objective

The investment objective of the BlackRock Capital Appreciation Fund, Inc. (the “Fund”) is to seek long-term growth of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold BlackRock Shares of the Fund.

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses		BlackRock Shares BLACKROCK CAPITAL APPRECIATION FUND, INC.
Management Fee		0.61%
Distribution and/or Service (12b-1) Fees		none
Other Expenses		0.16%
Total Annual Fund Operating Expenses		0.77%
Fee Waivers and/or Expense Reimbursements	[1]	(0.05%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	[1]	0.72%

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	1 Year	3 Years	5 Years	10 Years
BlackRock Shares BLACKROCK CAPITAL APPRECIATION FUND, INC.	74	230	401	894

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 77% of the average value of its portfolio.

Principal Investment Strategies of the Fund

The Fund will seek to achieve its investment objective by investing primarily in a diversified portfolio consisting primarily of common stock of U.S. companies that Fund management believes have exhibited above-average growth rates in earnings over the long term. In other words, Fund management tries to choose investments that will increase in value over the long term.

The Fund will generally invest at least 65% of its total assets in the following equity securities:

• Common stock;

• Convertible preferred stock;

• Securities convertible into common stock; and

• Rights to subscribe to common stock.

Of these securities the Fund generally seeks to invest primarily in common stock.

The Fund may invest in companies of any size but emphasizes investments in companies that have medium to large stock market capitalizations (currently, approximately $2 billion or more).

Convertible securities generally are debt securities or preferred stock that may be converted into common stock. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock). A convertible’s value usually reflects both the stream of current income payments and the market value of the underlying common stock. The Fund may purchase securities pursuant to the exercise of subscription rights, which allow an issuer’s existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.

Principal Risks of Investing in the Fund

Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund.

• Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock.

• Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions.

• Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.

• Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.

• Mid Cap Securities Risk — The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.

Performance Information

The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. Effective June 28, 2010, the Fund reorganized with the BlackRock Capital Appreciation Portfolio (the “Predecessor Fund”), a series of BlackRock Funds^SM (the “Reorganization”), and the Predecessor Fund’s performance and financial history has been adopted by the Fund from the date of the Reorganization. The performance of BlackRock Shares of the Fund is based off of the performance of Institutional Shares of the Predecessor Fund, with no adjustments. On January 31, 2005, the Predecessor Fund reorganized with the State Street Research Legacy Fund (the “SSR Fund”), which had investment goals and strategies substantially similar to the Fund. For periods prior to January 31, 2005, the chart and table show performance information for the SSR Fund. The table compares the Fund’s performance to that of the Russell 1000^® Growth Index and the S&P 500^® Index, which are relevant to the Fund because they have characteristics similar to the Fund’s investment strategy. As with all such investments, past performance (before and after taxes) is not an indication of future results. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at (800) 882-0052.

BlackRock Shares
ANNUAL TOTAL RETURNS
BlackRock Capital Appreciation Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 16.64% (quarter ended September 30, 2009) and the lowest return for a quarter was –22.85% (quarter ended December 31, 2008).

As of 12/31/12
Average Annual Total Returns

Average Annual Total Returns BlackRock Shares	1 Year	5 Years	10 Years
BLACKROCK CAPITAL APPRECIATION FUND, INC.	14.29%	1.72%	7.42%
BLACKROCK CAPITAL APPRECIATION FUND, INC. Return After Taxes on Distributions	14.17%	1.69%	7.40%
BLACKROCK CAPITAL APPRECIATION FUND, INC. Return After Taxes on Distributions and Sale of Shares	9.46%	1.47%	6.56%
BLACKROCK CAPITAL APPRECIATION FUND, INC. Russell 1000® Growth Index (Reflects no deduction for fees, expenses or taxes)	15.26%	3.12%	7.52%
BLACKROCK CAPITAL APPRECIATION FUND, INC. Standard & Poor's (S&P) 500® Index (Reflects no deduction for fees, expenses or taxes)	16.00%	1.66%	7.10%

After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

[1] As described in the "Management of the Fund" section of the Fund's prospectus on page 19, BlackRock has contractually agreed to waive fees and/or reimburse expenses in order to limit the Fund's Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) for BlackRock Shares to 0.72% of average daily net assets until February 1, 2023. On February 1 of each year, the waiver agreement will renew automatically for an additional one year so that the agreement will have a perpetual ten year term. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested Directors of the Fund or by a vote of a majority of the outstanding voting securities of the Fund.