This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may be required to pay commissions and/or other forms of compensation to a broker for transactions in shares, which are not reflected in the tables or the examples below.

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys or sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These transaction costs, which are not reflected in the Annual Fund Operating Expenses or in the Examples, affect the Fund’s performance. The Fund has no operating history and therefore has no portfolio turnover information.

Other Expenses, New Fund, Based on Estimates [Text]

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Total “Other Expenses” are based on estimated amounts for the current fiscal year.

Expense Example [Heading]

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Examples

Expense Example Narrative [Text Block]

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The Examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Examples assume 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 Examples also assume that your investment has a 5% return each year and that the Fund’s operating expenses stay the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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PRINCIPAL STRATEGIES

Strategy Narrative [Text Block]

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The Fund is an actively-managed exchange-traded fund (“ETF”). The Adviser seeks to achieve the Fund’s investment objective by investing, under normal circumstances, at least 80% of its net assets in equity securities of issuers that are economically tied to emerging markets.

Emerging markets are countries considered to be developing countries by the international financial community and include, but are not limited to, those countries included in an emerging or frontier markets index by a recognized index provider, such as the MSCI Emerging Markets Index. An issuer may be considered to be economically tied to emerging markets if it: (i) is organized in or maintains its principal place of business, or has its shares principally traded on an exchange or market, in an emerging markets country; (ii) has significant business activities in an emerging markets country; or (iii) is a company that could be impacted by economic developments in an emerging markets country (both (ii) and (iii) could be based either on the location of a company’s business activities or assets, or sources of revenue, profits, or commercial inputs (such as raw materials, components, etc.). The Adviser may apply fundamental analysis in considering these factors when determining whether an issuer is economically tied to a particular country.

Equity securities in which the fund may invest include, but are not limited to, common stocks, preferred stocks, depositary receipts, real estate investment trusts (REITs), participation notes or other structured notes, and other instruments that provide exposure to equity securities.

The Fund invests in issuers that are determined by the Adviser to offer compelling profitability prospects, reasonable valuations, and favorable fundamental and quantitative trends. The Adviser employs an integrated approach that combines both fundamental and quantitative research to identify attractive investment opportunities and to manage risk. The Fund may invest in issuers of any market capitalization, industry or investment style.

Under most conditions, the Fund intends to have its assets invested among multiple emerging market countries, although the Fund may also invest in developed markets countries. In allocating the Fund’s assets among countries, the Advisor relies primarily on individual security selection driven by a bottom-up research process, though country-level factors are also considered.

Currency fluctuations can have a dramatic impact on equity returns, significantly adding to returns in some years and greatly diminishing them in others. The Fund will not typically hedge its currency exposure but has the ability to do so.

Risk [Heading]

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PRINCIPAL RISKS

Bar Chart and Performance Table [Heading]

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BAR CHART AND PERFORMANCE INFORMATION

Performance Narrative [Text Block]

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No performance information is presented for the Fund because it has not yet been in operation for a full calendar year.

Performance One Year or Less [Text]

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No performance information is presented for the Fund because it has not yet been in operation for a full calendar year.

AB Emerging Markets Opportunities ETF | Risk Lose Money [Member]

Risk/Return:

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Risk [Text Block]

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As with all investments, you may lose money by investing in the Fund.

AB Emerging Markets Opportunities ETF | Emerging Market Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Emerging Market Risk: Investments in foreign securities entail significant risks in addition to those customarily associated with investing in U.S. equities. These risks include risks related to unfavorable or unsuccessful government actions, reduction of government or central bank support, economic sanctions and tariffs and potential responses to those sanctions and tariffs, inadequate accounting standards and auditing and financial recordkeeping requirements, lack of information, social instability, armed conflict, and other adverse market, economic, political and regulatory factors, all of which could disrupt the financial markets in which the Fund invests and adversely affect the value of the Fund’s assets. These risks are heightened with respect to issuers in emerging-market countries because the markets are less developed, less liquid and subject to increased potential for market manipulation, and there may be a greater amount of economic, political and social uncertainty. These risks are even more pronounced in “frontier” markets, which are investable markets with lower total market capitalization and liquidity than the more developed emerging markets. Emerging markets typically have fewer medical and economic resources than more developed countries, and thus they may be less able to control or mitigate the effects of a pandemic, climate change, or a natural disaster.

AB Emerging Markets Opportunities ETF | Market Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Market Risk: The value of the Fund’s assets will fluctuate as the market or markets in which the Fund invests fluctuate. The value of the Fund’s investments may decline, sometimes rapidly and unpredictably, simply because of economic changes or other events, including public health crises (including the occurrence of a contagious disease or illness), terrorism, war, interest rate levels, tariffs and regional and global conflicts, that affect large portions of the market. It includes the risk that a particular style of investing may be underperforming the market generally.

AB Emerging Markets Opportunities ETF | Equity Securities Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Equity Securities Risk: The Fund invests in publicly-traded equity securities, and their value may fluctuate, sometimes rapidly and unpredictably, which means a security may be worth more or less than when it was purchased. These fluctuations can be based on a variety of factors including a company’s financial condition as well as macro-economic factors such as interest rates, inflation rates, global market conditions, and non-economic factors such as market perceptions and social or political events.

AB Emerging Markets Opportunities ETF | Foreign Non US Investments Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Foreign (Non-U.S.) Investments Risk: Investments in securities of non-U.S. issuers may involve more risk than those of U.S. issuers. These securities may fluctuate more widely in price and may be more difficult to trade than domestic securities due to adverse market, economic, political, regulatory or other factors.

AB Emerging Markets Opportunities ETF | Currency Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Currency Risk: Fluctuations in currency exchange rates may negatively affect the value of the Fund’s investments or reduce its returns.

AB Emerging Markets Opportunities ETF | Country Concentration Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Country Concentration Risk: The Fund may not be diversified among countries or geographic regions and the effect on the Fund’s net asset value, or NAV, of the specific risks identified above, such as political, regulatory and currency risks, may be magnified due to concentration of the Fund’s investments in a particular country or region, such as China. Risks of the Fund’s investments in securities of companies economically tied to China may include the volatility of the Chinese stock market, the Chinese economy’s heavy dependence on exports, and the continuing importance of the role of the Chinese Government. Recent developments in relations between the U.S. and China have heightened concerns of increased tariffs and restrictions on trade between the two countries. An increase in tariffs or trade restrictions, or even the threat of such developments, could lead to a significant reduction in international trade, which could have a negative impact on the economy of Asian countries and a commensurately negative impact on the Fund. China has a complex territorial dispute regarding the sovereignty of Taiwan and has made threats of invasion. Military conflict between China and Taiwan may adversely affect securities of Chinese, Taiwan-based and other issuers both in and outside the region. While the Chinese economy has grown at a rapid rate in recent years, the rate of growth has been declining, and there can be no assurance that China’s economy will continue to grow in the future.

AB Emerging Markets Opportunities ETF | China Single Country Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

China/Single Country Risk: Investments in issuers located in a particular country or geographic region typically involve more risk than investments in U.S. issuers because of particular market factors affecting that country or region, including political

instability, geopolitical risks or unpredictable economic conditions. Risks of the Fund’s investments in securities of companies economically tied to China may include the volatility of the Chinese stock market; the Chinese economy’s heavy dependence on exports, which may be affected adversely by trade barriers or disputes or may decrease, sometimes significantly, when the world economy weakens; and the continuing importance of the role of the Chinese Government, which may take legal or regulatory actions that affect the contractual arrangements of a company or economic and market practices, and cause the value of the securities of an issuer held by the Fund to decrease significantly. Recent developments in relations between the U.S. and China have heightened concerns of increased tariffs and restrictions on trade between the two countries. An increase in tariffs or trade restrictions, or even the threat of such developments, could lead to a significant reduction in international trade, which could have a negative impact on the economy of Asian countries and a commensurately negative impact on the Fund. In addition, the Fund’s investments in companies owned or controlled directly or indirectly by the central, provincial or municipal governments of the People’s Republic of China or by the People’s Liberation Army (the military arm of the Chinese Communist Party) involve risks that political changes, social instability, regulatory uncertainty, adverse diplomatic developments, asset expropriation or nationalization, economic sanctions, trade embargos, cancellation of investors’ interests, or confiscatory taxation could adversely affect the performance of such companies and therefore investments by the Fund in those companies. China has a complex territorial dispute regarding the sovereignty of Taiwan and has made threats of invasion. Military conflict between China and Taiwan may adversely affect securities of Chinese, Taiwan-based and other issuers both in and outside the region. While the Chinese economy has grown at a rapid rate in recent years, the rate of growth has been declining, and there can be no assurance that China’s economy will continue to grow in the future. Investments in China A shares are subject to various licenses and quotas that may restrict daily trading and to additional risks that could affect liquidity compared to investments in companies in developed markets. Risks of investments in companies based in Hong Kong include heavy reliance on the Chinese economy, plus regional Asian and global economies such as the U.S. economy, which makes these investments vulnerable to changes in these economies.

AB Emerging Markets Opportunities ETF | Allocation Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Allocation Risk: The allocation of Fund assets among different asset classes, such as equity securities, debt securities and currencies, may have a significant adverse effect on the Fund’s NAV when one of these asset classes is performing better or worse than others. The diversification benefits typically associated with investing in both equity and debt securities may be limited in the emerging markets context, as movements in emerging market equity and emerging market debt markets may be more correlated than movements in the equity and debt markets of developed countries.

AB Emerging Markets Opportunities ETF | Capitalization Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Capitalization Risk: Investments in mid-capitalization companies may be more volatile than investments in large-capitalization companies. Investments in mid-capitalization companies may have additional risks because these companies have limited product lines, markets or financial resources.

AB Emerging Markets Opportunities ETF | Derivatives Risks [Member]

Risk/Return:

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Risk [Text Block]

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•

Derivatives Risk: Derivatives may be difficult to price or unwind and may be leveraged so that small changes may produce disproportionate losses for the Fund. A short position in a derivative instrument involves the risk of a theoretically unlimited increase in the value of the underlying asset, reference rate or index, which could cause the Fund to suffer a potentially unlimited loss. Derivatives, especially over-the-counter derivatives, are also subject to counterparty risk, which is the risk that the counterparty (the party on the other side of the transaction) on a derivative transaction will be unable or unwilling to honor its contractual obligations to the Fund.

AB Emerging Markets Opportunities ETF | Actions by a Few Major Investors [Member]

Risk/Return:

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Risk [Text Block]

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•

Actions by a Few Major Investors: In certain countries, volatility may be heightened by actions of a few major investors. For example, substantial increases or decreases in cash flows of funds investing in these markets could significantly affect local stock prices and, therefore, share prices of the Fund.

AB Emerging Markets Opportunities ETF | Sector Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Sector Risk: The Fund may have more risk because it may invest to a significant extent in one or more particular market sectors, such as the information technology or financials sector. To the extent it does so, market or economic factors affecting the relevant sector(s) could have a major effect on the value of the Fund’s investments.

AB Emerging Markets Opportunities ETF | Cash Transactions Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Cash Transactions Risk: The Fund intends to effectuate all or a portion of the issuance and redemption of Creation Units (as defined below) for cash, rather than in-kind securities. As a result, an investment in the Fund is expected to be less tax-efficient than an investment in an ETF that effectuates its transactions in Creation Units primarily on an in-kind basis. A fund that effects redemptions for cash may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. Any recognized gain on these sales by the Fund will generally cause the Fund to recognize a gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required as compared to an ETF that distributes portfolio securities in-kind in redemption of Creation Units. The Fund intends to distribute gains that arise by virtue of the issuance and redemption of Creation Units being effectuated in cash to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with applicable tax requirements. This may cause shareholders to be subject to tax on gains to which they would not otherwise be subject, or at an earlier date than if they had made an investment in another ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. Brokerage fees, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to those purchasing and redeeming Creation Units in the form of creation and redemption transaction

fees. In addition, these factors may result in wider spreads between the bid and ask prices of Fund shares than for ETFs that receive and distribute portfolio securities in-kind. The Fund’s use of cash for creations and redemptions could also result in dilution to the Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objective.

AB Emerging Markets Opportunities ETF | ETF Share Price and Net Asset Value Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

ETF Share Price and Net Asset Value Risk: The Fund’s shares are listed for trading on the NYSE Arca, Inc. (“NYSE Arca” or the “Exchange”). Shares are generally bought and sold in the secondary market at market prices. The NAV per share of the Fund will fluctuate with changes in the market value of the Fund’s holdings. The Fund’s NAV is calculated once per day, at the end of the day. The market price of a share on the Exchange could be higher than the NAV (premium), or lower than the NAV (discount) and may fluctuate during the trading day. When all or a portion of the Fund’s underlying securities trade in a market that is closed when the market for the Fund’s shares is open, there may be differences between the current value of a security and the last quoted price for that security in the closed local market, which could lead to a deviation between the market value of the Fund’s shares and the Fund’s NAV. Disruptions in the creations and redemptions process or the existence of extreme market volatility could result in the Fund’s shares trading above or below NAV. As the Fund may invest in securities traded on foreign exchanges, Fund shares may trade at a larger premium or discount to the Fund’s NAV per share than shares of other ETFs. In addition, in stressed market conditions, the market for Fund shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s underlying portfolio holdings.

AB Emerging Markets Opportunities ETF | Authorized Participant Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Authorized Participant Risk: Only a limited number of financial institutions that enter into an authorized participant relationship with the Fund (“Authorized Participants”) may engage in creation or redemption transactions. If the Fund’s Authorized Participants decide not to create or redeem shares, Fund shares may trade at a larger premium or discount to the Fund’s NAV per share, or the Fund could face trading halts or de-listing.

AB Emerging Markets Opportunities ETF | Active Trading Market Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Active Trading Market Risk: There is no guarantee that an active trading market for Fund shares will exist at all times. In times of market stress, markets can suffer erratic or unpredictable trading activity, extraordinary volatility or wide bid/ask spreads, which could cause some market makers and Authorized Participants to reduce their market activity or “step away” from making a market in ETF shares. Market makers and Authorized Participants are not obligated to place or execute purchase and redemption orders. This could cause the Fund’s market price to deviate, materially, from the NAV, and reduce the effectiveness of the ETF arbitrage process. Any absence of an active trading market for Fund shares could lead to a heightened risk that there will be a difference between the market price of a Fund share and the underlying value of the Fund share.

AB Emerging Markets Opportunities ETF | Management Risk [Member]

Risk/Return:

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Risk [Text Block]

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•

Management Risk: The Fund is subject to management risk because it is an actively-managed ETF. The Adviser will apply its investment techniques and risk analyses in making investment decisions, but there is no guarantee that its techniques will produce the intended results. Some of these techniques may incorporate, or rely upon, quantitative models, but there is no guarantee that these models will generate accurate forecasts, reduce risk or otherwise perform as expected.

AB Emerging Markets Opportunities ETF | AB Emerging Markets Opportunities ETF

Risk/Return:

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Shareholder Fees (fees paid directly from your investment)

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none

Management Fees

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0.70%

^[1]

Distribution and/or Service (12b-1) Fees

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none

Other Expenses

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none

^[2]

Total Annual Fund Operating Expenses

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0.70%

After 1 Year

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$ 72

After 3 Years

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$ 224

[1]

The Fund’s investment advisory agreement provides that AllianceBernstein L.P. (the “Adviser”) will pay substantially all expenses of the Fund (including expenses of AB Active ETFs, Inc. relating to the Fund), except for the advisory fees, payments under the Fund’s 12b-1 plan (if any), interest expenses, taxes, acquired fund fees and expenses (other than fees and expenses for funds advised by the Adviser and/or its affiliates), and litigation and extraordinary expenses not incurred in the ordinary course of the Fund’s business. Additionally, the Fund shall be responsible for its non-operating expenses, including brokerage commissions.

[2]

Total “Other Expenses” are based on estimated amounts for the current fiscal year.