The fund is an actively managed ETF that operates pursuant to an exemptive order from the Securities and Exchange Commission (Order) and is not required to publicly disclose its complete portfolio holdings each business day. Instead, the fund publishes each business day on its website a "Tracking Basket," which is designed to closely track the daily performance of the fund but is not the fund's actual portfolio. The Tracking Basket is comprised of: (1) select recently disclosed portfolio holdings and/or select securities from the universe from which the fund's investments are selected (Strategy Components); (2) liquid ETFs that convey information about the types of instruments (that are not otherwise fully represented by the Strategy Components) in which the fund invests (Representative ETFs); and (3) cash and cash equivalents. For additional information regarding the Tracking Basket, see "Additional Information about each Fund - Tracking Basket Structure" in the prospectus.The fund also publishes each business day on its website the "Tracking Basket Weight Overlap," which is the percentage weight overlap between the holdings of the prior business day's Tracking Basket compared to the holdings of the fund that formed the basis for the fund's calculation of net asset value per share (NAV) at the end of the prior business day. The Tracking Basket Weight Overlap is designed to provide investors with an understanding of how similar the Tracking Basket is to the fund's actual portfolio in percentage terms.Normally investing primarily in equity securities.Normally investing at least 80% of assets in equity securities of U.S. companies that Fidelity Management & Research Company LLC (FMR) (the Adviser) believes have proven or improving sustainability practices based on an evaluation of such companies' individual environmental, social, and governance (ESG) profile. An issuer is deemed to be located in the U.S. if the principal trading market for the security is in the United States or the issuer is organized under the laws of the United States.Using the Adviser's proprietary ESG ratings process to evaluate the current state of an issuer's sustainability practices using a data-driven framework that includes both proprietary and third-party data, and also provide a qualitative forward-looking assessment of an issuer's sustainability outlook provided by the Adviser's fundamental research analysts and ESG team. The Adviser's ESG ratings of issuers are derived from multiple factors, including an issuer's environmental profile, which may include, but is not limited to, carbon and toxic emissions, water management, waste management, vulnerability to the physical impacts of climate change, and research and investment into products, services, and energies that reduce emissions and/or provide opportunities to transition to less carbon-intensive products or operations. An assessment of an issuer's social profile includes, but is not limited to, its approach to diversity and inclusion, human capital management, data privacy, product safety and human rights. With respect to governance, the independence and diversity of an issuer's board, its compensation practices and board oversight of critical ESG issues are considered as part of the assessment. These factors are weighted based on how material the Adviser believes each factor is to an issuer's financial outlook, and not all factors may be applicable to all issuers.Investing in issuers that the Adviser believes deliver tangible environmental or social impact through core business operations. An assessment of the impact characteristics of an issuer may involve corporate engagement and an analysis of issuer alignment with the United Nations Sustainable Development Goals using qualitative analysis as well as proprietary or third-party data. For example, issuers that provide access to clean water, education, or clean energy through their core business may be considered to deliver tangible impact. Investing in securities of domestic and foreign issuers.In addition to the ESG ratings process, using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.Employing sustainable investing exclusion criteria to avoid investments in issuers that are directly engaged in, and/or derive significant revenue from, certain industries. Please see "Fund Basics - Investment Details - Sustainable Investing Exclusions" for additional information.