Topics / #polyfill

Polyfill projects on GitHub

Shims bringing modern browser APIs to older environments.

As of , the most-starred Polyfill projects on GitHub are rxjs (31.7K stars), fetch (25.8K stars) and core-js (25.5K stars). GitHub.Locker tracks 8 Polyfill repositories with 160.1K stars combined.

8Projects
160.1KStars in total
Browse in the catalog →github.com/topics/polyfill ↗

The all-time top

8 projects · by stars

  1. #1 · ReactiveX/rxjs

    rxjs

    RxJS is a JavaScript library for composing asynchronous and event-based programs with Observable values. This repo is the platform-based next generation of RxJS, planned for release as RxJS 9.

    31.7K
  2. #2 · JakeChampion/fetch

    fetch

    A window.fetch polyfill — a Promise-based mechanism for making web requests in the browser, giving older browsers the fetch API as a replacement for XMLHttpRequest.

    25.8K
  3. #3 · zloirock/core-js

    core-js

    A modular standard library for JavaScript: polyfills for ECMAScript features up to 2025 — promises, symbols, collections, iterators, typed arrays — plus ECMAScript proposals and some WHATWG/W3C features like URL.

    25.5K
  1. 4

    FileSaver.js

    22Keligrey/FileSaver.js · JavaScript

    FileSaver.js is a client-side JavaScript library that implements the saveAs() interface, letting web apps trigger a file download for data generated right in the browser.

  2. 5

    fastclick

    18.5Kftlabs/fastclick · HTML

    A small open-source JavaScript library from FT Labs, part of the Financial Times. It removes the 300ms delay between a physical tap and the firing of the click event on mobile browsers, so apps feel less laggy and more responsive.

  3. 6

    formatjs

    14.7Kformatjs/formatjs · TypeScript

    FormatJS is a monorepo of JavaScript internationalization (i18n) libraries — message formatting, date/time/number formatting, and pluralization — with react-intl as its most popular package for React apps.

  4. 7

    Respond

    11.2Kscottjehl/Respond · JavaScript

    A fast, lightweight JavaScript polyfill that brings min/max-width CSS3 media query support to browsers that lack it — chiefly Internet Explorer 8 and under — so responsive web designs work there.

  5. 8

    history.js

    10.6Kbrowserstate/history.js · JavaScript

    A JavaScript library that makes the HTML5 History/State APIs (pushState, replaceState, onpopstate) work consistently in every browser: real URLs in HTML5 browsers, a hash-based fallback in old HTML4 ones.

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