Web Vitals

Discontinued

Google's Core Web Vitals extension

Google's official Chrome extension for measuring Largest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift on the current page in real time. Combines local measurements with field data from the Chrome UX Report so developers can see how their lab numbers compare to real user experience. Reached end-of-life in January 2025 as its functionality shipped into the Chrome DevTools Performance panel.

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About Web Vitals

The Web Vitals extension is a Chrome-based measurement tool built by the Google Chrome team to surface Core Web Vitals metrics — LCP, INP and CLS — as you browse. A toolbar badge flips between green, amber and red to reflect the current page's scores using the same methodology Chrome uses when reporting to PageSpeed Insights, Search Console and the Chrome UX Report. Clicking the icon opens a detailed panel with per-metric breakdowns, contributing elements and debugging information.

A distinguishing feature is its integration with the Chrome UX Report (CrUX) API: the popup overlays your local experience against aggregated real-user data for the same origin, giving immediate context on whether a problem is specific to your machine or systemic across users. The extension also offers an overlay HUD showing metrics live while you interact with the page — invaluable when diagnosing layout shifts, slow paints or laggy input handling without opening DevTools.

Google announced end of life for the standalone extension on January 7, 2025, after the same capabilities (and additional real-time metrics) landed natively in the Chrome DevTools Performance panel in Chrome 129+. The source code remains on GitHub at GoogleChrome/web-vitals-extension for teams that still rely on it, and the underlying web-vitals JavaScript library continues as the canonical way to measure Core Web Vitals programmatically in production.

Pricing & Platform Specs

Pricing Summary

100% Free and Open Source (Apache-2.0) Chrome extension by Google ($0). Provides real-time in-browser measurement for Core Web Vitals (LCP, INP, CLS). Core functionality is also natively integrated into Chrome DevTools Performance panel.

Supported Platforms

Chrome

Why it was discontinued

discontinued January 7, 2025

Google ended support for the standalone Web Vitals Chrome extension in Chrome 132 (stable, January 7, 2025); its real-time Core Web Vitals overlay was merged natively into Chrome DevTools' Performance panel. The extension is no longer updated, and its CrUX API key integration faces revocation. Developers should use the built-in DevTools Performance panel or the web-vitals JavaScript library directly instead.

use instead: React DevTools, Vue DevTools, Responsively

Explore categories, tags & use cases

Use Cases

Testing & QA Automation

Alternatives

All Web Vitals alternatives →

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Official browser DevTools extension for Vue.js providing deep inspection of component trees, reactive state, props, events, and slots. Includes Pinia/Vuex store debugging with time-travel, Vue Router inspection, performance timeline, and component highlighting. Works with Vue 2 and Vue 3. Available for Chrome and Firefox with standalone Electron app. Essential for debugging reactivity and understanding component hierarchies in Vue applications.

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Open Source

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Community experience

Sources & verification

Web Vitals Official Documentation & Repository

Sources checked: September 5, 2026
Content verified: September 6, 2026

Verification dates are editorial checks. Routine CMS saves and automatic updatedAt timestamps do not advance them.

FAQ

What is Web Vitals?

Is Web Vitals free?

Yes — Web Vitals is open source and free to use. 100% Free and Open Source (Apache-2.0) Chrome extension by Google ($0). Provides real-time in-browser measurement for Core Web Vitals (LCP, INP, CLS). Core functionality is also natively integrated into Chrome DevTools Performance panel.

Is Web Vitals open source?

Yes — Web Vitals is open source.

Is Web Vitals still available?

No — Web Vitals was discontinued on January 7, 2025. Google ended support for the standalone Web Vitals Chrome extension in Chrome 132 (stable, January 7, 2025); its real-time Core Web Vitals overlay was merged natively into Chrome DevTools' Performance panel. The extension is no longer updated, and its CrUX API key integration faces revocation. Developers should use the built-in DevTools Performance panel or the web-vitals JavaScript library directly instead. Consider React DevTools, Vue DevTools, Responsively instead.

What are the best Web Vitals alternatives?

The first editor-selected Web Vitals alternatives are React DevTools, Vue DevTools, Responsively.

Web Vitals

About Web Vitals

Pricing & Platform Specs

Pricing Summary

Supported Platforms

Why it was discontinued

Categories

Tags

Use Cases

Alternatives

React DevTools

Vue DevTools