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Explainer No information provided Specification https://wicg.github.io/background-fetch Summary Deprecates the Background Fetch API, which allows web applications to download large files in the background, even if the user navigates away from the page or closes the browser. Despite being available in Chrome since version 74, the Background Fetch API has not seen wide adoption by the developer community, with usage remaining consistently low, at less than 0.00002% of page loads as of November 2025. Given the low adoption rate and the significant engineering effort required to maintain the API and address ongoing security issues, it is being deprecated. Developers are encouraged to explore alternative solutions for managing large file downloads. Blink component Blink>ServiceWorker Web Feature ID background-fetch Motivation The Background Fetch API has been available in Chrome since version 74. However, it has not seen wide adoption. Usage metrics show that the feature is used in less than 0.00002% of page loads as of November 2025. Given the low usage, the ongoing engineering effort to maintain the Background Fetch API and address security issues is no longer justifiable. For developers who need to provide users with the ability to download large files, there are several alternatives: - For simple file downloads, developers can provide a standard download link. - For more advanced use cases, such as providing offline access to large files, developers can use the Fetch API within a Service Worker to download and cache the necessary resources. This approach provides developers with greater control over the user experience. Initial public proposal No information provided TAG review No information provided TAG review status Not applicable Risks Interoperability and Compatibility The interoperability risk of removing the Background Fetch API is low. The API has not been implemented by Firefox or Safari, and there have been no signals from either to indicate that they intend to do so. As a result, removing this API from Chrome will not cause interoperability issues, as it is not a feature that is part of the interoperable web platform. The compatibility risk is also minimal. Usage of the Background Fetch API has remained consistently low, at less than 0.00002% of page loads as of November 2025. Because of this extremely low usage, the number of websites that will be affected by this removal is very small. Gecko: No signal (https://github.com/mozilla/standards-positions/issues/30) WebKit: No signal (https://github.com/WebKit/standards-positions/issues/149) Web developers: No signals Other signals: TAG: https://github.com/w3ctag/design-reviews/issues/279 Ergonomics The Background Fetch API is tightly coupled with the Service Worker API. It is accessed through the backgroundFetch property of a ServiceWorkerRegistration object. Developers using this API would also likely use the Fetch API to create the Request objects for the download and the Cache API to store the downloaded responses. The API is designed to be asynchronous and to operate in the background. The main fetch() method returns a Promise, and the download process is managed by the browser, off the main thread. This design avoids blocking the main thread and is intended to improve performance and battery life for large downloads compared to keeping a service worker alive for a long-running fetch. Therefore, the API's usage does not inherently pose a performance risk that would make it difficult for Chrome to maintain good performance. The deprecation is due to low adoption and high maintenance cost, not because of ergonomic or performance issues in its design. Activation This change is a deprecation and removal of an existing API. The primary risk is the impact on developers who are currently using the Background Fetch API. However, the "activation" risk for this removal is minimal. The API has seen extremely low adoption since its introduction in Chrome 74, with usage below 0.00002% of page loads. This indicates that very few developers will be required to take action. Security The removal of the Background Fetch API reduces the overall attack surface of the browser and mitigates existing security issues associated with maintaining the feature. WebView application risks Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications? No information provided Debuggability No information provided Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)? No Is this feature fully tested by web-platform-tests? No Flag name on about://flags No information provided Finch feature name BackgroundFetch Rollout plan Will ship enabled for all users Requires code in //chrome? False Tracking bug https://crbug.com/460293588 Estimated milestones Shipping on desktop 146 Shipping on Android 146 Shipping on WebView 146 Anticipated spec changes Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (eg links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (eg, changing to naming or structure of the API in a non-backward-compatible way). No information provided Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5074579353632768?gate=6606728540061696 This intent message was generated by Chrome Platform Status. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6925253c.050a0220.107b62.0899.GAE%40google.com.
