Measure and report on your Web Vitals data in Google Analytics

Essential metrics for a healthy site.

Demos showing how to use Import Maps to prevent cascading cache invalidations

A fast, tiny polyfill for dynamic import() that works in all module-supporting browsers

ESLint shareable config for the Google JavaScript style guide

📦 Workbox: JavaScript libraries for Progressive Web Apps

A demo app showcasing the use of real JavaScript modules in production—complete with cross-browser fallbacks for legacy browsers.

Helper classes and methods for implementing the idle-until-urgent pattern

PageLifecycle.js is a tiny JavaScript library that allows developers to easily observe Page Lifecycle API state changes cross browser

Time-to-interactive polyfill

Examples and best practices for using analytics.js

A proof-of-concept for building CSS polyfills

Easily run JavaScript unit tests on the Sauce Labs cloud.

Automatic and enhanced Google Analytics tracking for common user interactions on the web.

Easily get and set the text selection with an HTML element.

A community-curated list of flexbox issues and cross-browser workarounds for them.

Google Analytics web components

A simple router that binds URLs paths and patterns to functions.

A showcase of demos and tools built with the various Google Analytics APIs and Libraries.

A full-featured, classical inheritance library for Node.js and the browser.

A simple and intuitive way to shim private methods and properties in JavaScript.