In May, the Chrome team officially replaced First Input Delay (FID) with Interaction to Next Paint (INP) as the Core Web Vitals metric for assessing interaction responsiveness. Following an earlier announcement in January, Chrome has now fully ended support for FID in its performance tools.
What Stays the Same
Chromium will still support first-input entries in the PerformanceObserver API. Developers who wish to keep measuring FID in their applications can continue doing so using this API.
What’s Changing
FID data will no longer be available in various Chrome performance tools, including:
- PageSpeed Insights: FID data in the real-user experiences section will no longer be reported.
- PageSpeed Insights API: The
FIRST_INPUT_DELAY_MSmetric will no longer serve data. - CrUX APIs: The CrUX API and CrUX History API will discontinue FID metrics, and the CrUX Dashboard will remove the First Input Delay page.
- BigQuery Project: Starting with the October 2024 (202409) dataset, FID will be removed from the schema in the CrUX BigQuery project, although historical data will still be accessible.
- web-vitals.js Library: The
onFIDfunction will be removed in version 5.0, a major update. Stay updated by subscribing to release notifications in the library’s repository. - Web Vitals Extension: FID data will be removed from all extension surfaces, including the overlay panel and console logs.
Documentation Updates
The FID article on pixelcraftagencies will remain accessible for reference, but with a notice discouraging its use in favor of INP. The “Optimize FID” article will redirect to the “Optimize INP” article, as all recommended practices now align with INP.
Transitioning to INP
With this change, developers can fully embrace INP as the primary metric for measuring interaction responsiveness. This transition ensures that everyone is focusing on a metric that captures responsiveness more effectively than FID ever could.