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Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund seeks long-term capital growth.</span></div> Fees and Expenses <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">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.</span> 0.0039 0.0000 0.0039 Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other 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, 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: 40 126 219 493 Portfolio Turnover <div style="margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">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. During the most recent fiscal year, the fund’s portfolio turnover rate was 44% of the average value of its portfolio.</span></div> 0.44 Principal Investment Strategies <div><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The portfolio managers look for stocks of medium capitalization companies they believe will increase in value over time, using proprietary fundamental research. The portfolio managers make their investment decisions based primarily on their analysis of individual companies, rather than on broad economic forecasts.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">When evaluating a security’s potential for financial return, portfolio managers seek companies with attractive returns on invested capital that are demonstrating or expected to demonstrate long-term business improvement. Analytical indicators helping to identify or forecast signs of business improvement could include accelerating earnings or revenue growth rates, increasing cash flows, or other indications of the relative strength of a company’s business. This analysis supports the portfolio managers’ decisions to buy or hold the stocks of companies that meet their selection criteria and sell the stocks of companies whose characteristics no longer meet their criteria. Guided by this fundamental analysis, the advisor applies systematic risk controls and portfolio construction techniques to generate trade recommendations, which the portfolio managers use in an effort to improve efficiency, capacity, and liquidity.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund will invest principally in exchange-traded common stocks. Under normal market conditions, the portfolio managers will invest at least 80% of the fund’s assets in securities of medium-capitalization companies. The portfolio managers consider medium capitalization companies to include those whose market capitalizations at the time of purchase are within the total capitalization range of the Russell Midcap</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">®</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> Growth Index. Though market capitalizations will change from time to time, as of June 30, 2026, the fund considers companies with market capitalizations between $2.5 billion and $92.7 billion to be medium capitalization companies. The fund may purchase securities of small and large capitalization companies as well. The fund is nondiversified and normally invests in a relatively limited number of companies</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.</span></div>The fund is an actively managed exchange-traded fund (ETF) that does not seek to replicate the performance of a specified index. When deciding whether to buy or sell a security, and how and when to implement a trade, portfolio managers may consider the expected implementation costs and tax consequences of the trade in an attempt to gain trading efficiencies, avoid unnecessary risk, minimize tax impact, and/or enhance fund performance. The fund will invest principally in exchange-traded common stocks. Under normal market conditions, the portfolio managers will invest at least 80% of the fund’s assets in securities of medium-capitalization companies. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Authorized Participant Concentration Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> 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.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Nondiversification Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the portfolio managers the flexibility to hold large positions in a smaller number of securities. If so, a price change in any one of those securities may have a greater impact on the fund’s share price than would be the case in a diversified fund and the fund may be more volatile than if it was diversified.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Sector Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund. Companies in the same sector may be similarly affected by economic, regulatory, political or market events, or conditions, making the fund more vulnerable to unfavorable developments in that economic sector.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Growth Stocks Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> Investments in growth stocks may be more volatile than other stocks and the overall stock market. These stocks are typically priced higher than other stocks because of their growth potential, which may or may not be realized.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Mid Cap Stocks Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> The fund invests in medium-capitalization and smaller companies, which may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Style Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> If at any time the market is not favoring the fund’s growth investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Market Trading Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> 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.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Price Volatility Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> The value of the fund’s shares may fluctuate significantly in the short term.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Market Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> 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, war, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Large Shareholder Risk —</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> Certain shareholders, including other funds advised by the advisor, may from time to time own a substantial amount of the shares of the fund. In addition, a third-party investor, the advisor or an affiliate of the advisor, an authorized participant, a market maker, or another entity may invest in the fund and hold its investment for a limited period of time solely to facilitate commencement of the fund or to facilitate the fund’s achieving a specified size or scale. There can be no assurance that any large shareholder would not redeem its investment, that the size of the fund would be maintained at such levels or that the fund would continue to meet applicable listing requirements. Redemptions by large shareholders could have a significant negative impact on the fund. In addition, transactions by large shareholders may account for a large percentage of the trading volume on the Cboe BZX Exchange, Inc. (Cboe) and may therefore have a material upward or downward effect on the market price of the shares.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Principal Loss Risk — </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">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.</span><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">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.</span></div> Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Russell Midcap</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">®</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> Growth Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns Highest Performance Quarter 2024-03-31 0.1411 Lowest Performance Quarter 2022-06-30 -0.2130 2025-09-30 year-to-date return 0.1023 Average Annual Total Returns For the calendar year ended December 31, 2024 Return Before Taxes 0.1940 0.1065 2020-07-13 Return After Taxes on Distributions 0.1935 0.1064 2020-07-13 Return After Taxes on Distributions and Sale of Fund Shares 0.1152 0.0843 2020-07-13 Russell 3000® Index  (reflects no deduction for fees, expenses or taxes) (reflects no deduction for fees, expenses or taxes) 0.2381 0.1614 Russell Midcap® Growth Index  (reflects no deduction for fees, expenses or taxes) 0.2210 0.1175 <div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">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 an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.</span></div> 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 an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.