The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

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 and 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 costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. Because the fund is new, the fund’s portfolio turnover rate is not available.

Expense Exchange Traded Fund Commissions [Text]

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You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

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

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Other expenses are based on estimated amounts for the current fiscal year

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other funds.

Expense Example by, Year, Caption [Text]

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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 (unless otherwise indicated), that you earn 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]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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Portfolio managers utilize quantitative models to select securities with attractive fundamentals that they expect will provide enhanced risk-adjusted returns over the long term, while realizing less volatility.

The fund generally invests in common stocks of U.S. companies that have a market capitalization greater than $2 billion. To select securities for the fund, portfolio managers utilize proprietary models to screen and rank companies based on fundamental metrics. The information used to generate these measures is typically contained in financial statement data and market information, but may include other sources. The fund seeks to deliver a lower realized portfolio volatility than its benchmark, the S&P 500® Index, by utilizing a stock selection process that expands on traditional measures of price volatility by including measures of asymmetric (i.e. downside) volatility and seeking securities of businesses that demonstrate consistent cash-flows, stable operations, and strong balance sheets. Portfolio managers employ a multi-dimensional approach to stock selection and risk management—which includes evaluating empirical measures of stock price risks and fundamental measures of business safety and continuity—to construct a portfolio that balances the return and risk objectives of the fund. This approach seeks to identify risks of individual securities and across key dimensions such as economic segment. Finally, portfolio managers review the output of the quantitative model, considering factors such as risk management, transaction costs, and liquidity management.

The portfolio managers generally sell securities from the fund’s portfolio when they believe a security becomes less attractive relative to other opportunities, a security’s risk characteristics outweigh its return opportunity, or specific events alter a security’s prospects.

The fund is an actively managed exchange-traded fund (ETF) that does not seek to replicate the performance of a specified index. When buying or selling a security, the portfolio managers may consider the trade-off between expected returns of the security and implementation or tax costs of the trade in an attempt to gain trading efficiencies, avoid unnecessary risk, and enhance fund performance.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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Low Volatility Strategy Risk - There is no assurance that the fund will be less volatile than the market over the long term or for any specified period. The fund’s strategy of constructing a portfolio that realizes lower volatility than the market may not produce the intended result. A security’s volatility can change very quickly, and specific securities in the fund’s portfolio may become more

volatile than expected. Additionally, low volatility investments may underperform the equity markets during periods of strong, rising or speculative equity markets.

•Equity Securities Risk - The value of equity securities, may fluctuate due to changes in investor perception of a specific issuer, changes in the general condition of the stock market, or occurrences of political or economic events that affect equity issuers and the market. Common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

•Investment Process Risk – Securities selected by the portfolio managers may perform differently than expected due to the portfolio managers’ judgments regarding the factors used, the weight placed on each factor, changes from the factors’ historical trends, and technical issues with the construction and implementation of the investment process (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the investment process will result in effective investment decisions for the fund.

•Cash Transactions Risk - The fund may effect its creations and redemptions for cash, rather than for in-kind securities. Therefore, it may be required to sell portfolio securities and subsequently recognize gains on such sales that the fund might not have recognized if it were to distribute portfolio securities in-kind. As such, investments in fund shares may be less tax-efficient than an investment in an ETF that distributes portfolio securities entirely in-kind. 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 and taxes could be higher than if the fund sold and redeemed shares in-kind.

•Market Trading Risk - The fund faces numerous market trading risks, including the potential lack of an active market for fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation and/or redemption process of the fund. Any of these factors, among others, may lead to the fund’s shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than NAV when you buy shares of the fund in the secondary market, and you may receive less (or more) than NAV when you sell those shares in the secondary market. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.

•Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.

•Public Health Emergency Risk - A pandemic, caused by the infectious respiratory illness COVID-19, is leading to travel restrictions, disruption of healthcare systems, prolonged quarantines, cancellations, supply chain disruptions, lower consumer demand, layoffs, ratings downgrades, and defaults among other economic impacts. Certain markets have experienced temporary closures, extreme volatility, severe losses, reduced liquidity and increased trading costs. These events may continue to impact the fund and its underlying investments and could cause increased premiums or discounts to the fund’s NAV.

•Authorized Participant Concentration Risk - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund may have a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the fund and no other authorized participant is able to step forward to process creation and/or redemption orders, fund shares may trade at a discount to net asset value (NAV) and possibly face trading halts and/or delisting. This risk may be more pronounced in volatile markets, potentially where there are significant redemptions in ETFs generally.

•Redemption Risk - The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.

•Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

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Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

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An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

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Fund Performance

Performance Narrative [Text Block]

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The fund’s performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund. This information indicates the volatility of the fund’s historical returns from year to year. For current performance information, please visit americancenturyetfs.com.

Performance information is designed to help you see how fund returns can vary. Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

Performance Information Illustrates Variability of Returns [Text]

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Performance information is designed to help you see how fund returns can vary.

Performance One Year or Less [Text]

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Performance Availability Website Address [Text]

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americancenturyetfs.com

Performance Past Does Not Indicate Future [Text]

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Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

American Century ETF Trust | American Century Low Volatility ETF | American Century Low Volatility ETF