JSPM

Polyfill the ECMA-402 Intl API (except collation)

ES2015 (ES6) Number.isInteger polyfill

Smooth Scroll behavior polyfill

Polyfill/shim for `document.contains`

a simple polyfill for javascript URLSearchParams

Ensure a path doesn't contain null bytes

Return the prototype of a provided object.

A polyfill for creating CustomEvents on IE9+ if the native implementation is missing.

ECMAScript6 WeakMap polyfill

Ponyfill for ES2020 Intl.NumberFormat

Comprehensive TypeScript/JavaScript utility library with cross-environment support (Node.js, browser, web worker) providing helper functions, polyfills (ES5-ES2023), type checking utilities, and optimized implementations for better minification and code r

EventSource polyfill for browser and node.js

Cross-browser JavaScript shim that fully implements element.classList (referenced on MDN)

Polyfill for perf_hooks.monitorEventLoopDelay(...)

Intl.MessageFormat / Unicode MessageFormat 2 parser, runtime and polyfill

Polyfills nodejs builtin modules and globals for the browser.

Blob.js implements the W3C Blob interface in browsers that do not natively support it.

Polyfill for Intl.PluralRules

Test whether a path exists on the filesystem.

A browser polyfill for W3C EventSource (http://www.w3.org/TR/eventsource/)

Mouse state change listener

Cross browser mouse event property access

JavaScript implementation of the Web Animations API

Intl.DateTimeFormat polyfill

Polyfill for Scoped CSS

The URLSearchParams polyfill.

HTML Custom Elements Polyfill

A Javascript polyfill for browsers that don't support the object-fit CSS property

Web Components Polyfills

Promise.witResolvers() polyfill

An implementation and polyfill of the Resize Observer draft.

Return the closest element matching a selector up the DOM tree

An ES5 spec-compliant `Array.prototype.every` shim/polyfill/replacement that works as far down as ES3.

A polyfill for the encryptionScheme field in EME

A robust ES3-compatible polyfill for the `RegExp.escape` proposal - see https://github.com/tc39/proposal-regex-escaping

Client-side support for CSS custom properties (aka "CSS variables") in legacy and modern browsers

A polyfill for the asynchronous clipboard API

WebGL2 API Polyfills for WebGL1 WebGLRenderingContext

A BroadcastChannel that works in New Browsers, Old Browsers, WebWorkers

ES 2021 spec-compliant shim for Promise.any

Constructible style sheets/adopted style sheets polyfill

A Barcode Detection API polyfill that uses ZXing webassembly under the hood

Ponyfill for smooth scrolling elements into view (if needed!)

Deno namespace shim for Node.js

Polyfill for the Proxy object

Polyfill object-fit and object-position on images on IE9, IE10, IE11, Edge, Safari, ...

A polyfill for the proposed inert API

Wrapper for the Page Visibility API

An ES spec-compliant `Array.prototype.forEach` shim/polyfill/replacement that works as far down as ES3.

Polyfill for navigator.sendBeacon()

Polyfill for RFC 566: @cached

An ES-spec-compliant (proposed) Array.prototype.at shim/polyfill/replacement that works as far down as ES3

A fork of create-react-context in MIT license

Polyfill for RFC 580: Destroyables

Polyfill requestAnimationFrame and cancelAnimationFrame

A robust & optimized `String.prototype.startsWith` polyfill, based on the ECMAScript 6 specification.

MediaRecorder polyfill to record audio in Edge and Safari

Popover Attribute Polyfill

This package includes the [core-js](https://github.com/zloirock/core-js) polyfill for `String#replaceAll`, along with TypeScript typings.

polyfill for `KeyboardEvent.prototype.key`

Polyfill for the basic functionality of `Function.name` accessor property in its pre-ES6 form

A polyfill for Ember CLI's TypeScript blueprint capabilities.

An ES5 mostly-spec-compliant `Object.getPrototypeOf` sham/polyfill/replacement that works in as many engines as possible

A polyfill for the Record and Tuple Stage 2 ECMAScript proposal.

Javascript Error Polyfill

A cross browser solution to scrolling during drag and drop.

JavaScript polyfill for the WHATWG spec of focusOptions, that enables a set of options to be passed to the focus method.

Smooth Scroll behavior polyfill

A Javascript utility library for working with native objects.

A polyfill for the element internals specification

PostCSS plugin for Flexibility polyfill

CSSOM-valid and jsdom/Jest-compatible matchMedia polyfill for server-side unit tests

A JavaScript polyfill for Flexbox

CanvasRenderingContext2D.roundRect() and Path2D.roundRect() polyfill

Transit is a data format and a set of libraries for conveying values between applications written in different languages. This library provides support for marshalling Transit data to/from Javascript.

Standard library

MDN polyfills

A polyfill for Ember.assign in <= 2.4

A polyfill for the 'scroll-behavior' CSS-property

Polyfill for ES6 Promise

Polyfill for CSS `position: sticky`

Quick wrapper that finds TextDecoder or polyfills a bad implementation

A polyfill for crypto.randomFill and crypto.randomFillSync from Node.js core

Replaces `arr.includes(val)' with `arr.indexOf(val) >= 0`.

A minimal polyfill for Element.closest

Super small `Element.matches` fix for older browsers (IE 9+, Edge 12+, Safari, Android browsers)

ECMAScript 7 compatibility shims for legacy JavaScript engines

Round a double-precision floating-point number toward zero.

Returns the first index at which a given element can be found.

Node's util.inspect, extracted for use on the Web

Return the first index at which a given element can be found.

<form>.requestSubmit() polyfill

W3C's Fullscreen API Polyfill

Simple ES6 Object.assign() polyfill for older environments.

User Timing polyfill

Polyfill for making HTML5 drag and drop possible in all browsers.

A polyfill that fetches external SVGs referenced in use elements when the browser itself fails to do so.

Provide helpers that polyfill all methods defined in [iterator helpers proposal](https://github.com/tc39/proposal-iterator-helpers), both for `Iterator` and `AsyncIterator`, and even more.

Browser polyfill for making React Native compatible with web libs like pixi.js, three.js, phaser.js

A polyfill for the Resize Observer API

Object.fromEntries() polyfill

All inclusive customElements polyfill for every browser

Scoped CustomElementRegistry Polyfill

A robust & optimized `String.prototype.endsWith` polyfill, based on the ECMAScript 6 specification.

HTML <details> element polyfill

WebAssembly interpreter

An ES-spec-compliant shim/polyfill/replacement for the `.cause` property on all Error types that works as far down as ES3

Validate your forms, frontend, without writing a single line of javascript!

An EventTarget polyfill

Runtime polyfills for TypeScript libs, powered by core-js!

Polyfill/shim for stream.finished in node versions < v10

`Object.entries()` ponyfill

Polyfill for the proposed CSS anchor positioning spec

A polyfill for the native import() in the browser

An ESnext spec-compliant `DisposableStack`, `AsyncDisposableStack`, `Symbol.dispose`, and `Symbol.asyncDispose` shim/polyfill/replacement that works as far down as ES3.

An ES-spec-compliant Set shim/polyfill/replacement that works as far down as ES3

Polyfill/shim for stream.pipeline in node versions < v10

Compatibility layer for efficient streaming of binary data using [WHATWG Streams](https://streams.spec.whatwg.org/)

React component for anchor links using the smoothscroll polyfill.

Object.setPrototypeOf Polyfill

An ESnext spec-compliant `Set.prototype.difference` shim/polyfill/replacement that works as far down as ES3

A polyfill of IntersectionObserver API

fs.promises polyfill

A browser polyfill for W3C EventSource (http://www.w3.org/TR/eventsource/)

ES Proposal spec-compliant shim for SuppressedError

Patches global.Promise to use bluebird and returns a bluebird instance

polyfill for es8 Object.values

Cross-browser implementation of W3C saveAs API

Tiny Web Share API Wrapper with fallback for unsupported browsers

A cross browser solution to scrolling during drag and drop.

Polyfills and patches missing or partially supported web and core APIs

An ES-spec-compliant Map shim/polyfill/replacement that works as far down as ES3

Polyfills the a[download] attribute

Standardizer for node's console.assert

The minimal set of polyfills that the Aurelia platform needs to run on ES5 browsers.

Compute the arcsine of a double-precision floating-point number.

ECMAScript Map like object.

Polyfill for scrollend event

An ES5 spec-compliant `Array.prototype.some` shim/polyfill/replacement that works as far down as ES3.

get-own-property-symbols ========================

A fully spec-compliant polyfill for 'Intl.ListFormat'

Simple, small and fast jQuery polyfill for the HTML5 <input type="range"> slider element

Determines whether a string ends with the characters of another string.

Small vanilla javascript that feature detect the :focus-within pseudo selector and polyfills it with a standard css class if necessary.

Polyfill for BroadcastChannel for Safari, old Chrome and Opera

An accessible polyfill for `[input type='time']` elements modeled after the Chrome & Firefox desktop implementations.

A canvas.toBlob() implementation

Polyfill to provide array.find on IE.

Polyfill Web Speech API with Cognitive Services Speech-to-Text service

Cross-platform Blob implementation for NodeJS and the Web.

A jquery polyfill for the old, removed $.live() method

A polyfill for the proposed blocking elements stack API

TypeScript shim for DOMMatrix

Compute the arccosine of a double-precision floating-point number.

React.createRef() polyfill

PostCSS plugin that updates the standard object-fit tag to work with the object-fit-images polyfill for browsers that do not natively support object-fit.

Return elements matching a selector relative to the current node

An trim polyfill for legacy browsers.

An essential WeakMap polyfill for legacy browsers.

Run ES Module syntax in any browser – even IE!

Simple polyfill for the NodeList.forEach method.

`core-js`'s `web/url.js` prebundled for the browser

An Object.fromEntries polyfill

High performance WebRTC polyfill for Node.JS via libdatachannel using Node Native/NAPI.

A polyfill for the Cookie Store API

console.time, console.timeLog and console.timeEnd polyfill for react-native

CSS.supports() shim

Polyfill for the HTML5 `<details>` element

An importNode polyfill for IE11 and other legacy browsers

Ember cli addon that includes a polyfill for closest() if needed.

W3C compliant EventSource client for Node.js and browser (polyfill)

A simple SDP interoperability layer for Unified Plan/Plan B

ES2015 WeakMap polyfill for Ember.WeakMap

An ESnext spec-compliant `Set.prototype.intersection` shim/polyfill/replacement that works as far down as ES3

Tiny KeyboardEvent#key shim for IE and MS Edge

A small mostly spec. compliant polyfill/ponyfill for SharedWorkers, it acts as a drop in replacement for normal Workers, and supports an API surface that matches normal Workers.

Plugin for injecting a polyfills loader to HTML pages

Web Streams, based on the WHATWG spec reference implementation

A minimal polyfill for Element scroll extensions.

Canvas toBlob polyfill

html5 storage interface for node and browser

A polyfill for missing Object.values / Object.entries

Polyfill for SVG 2 getPathData() and setPathData() methods

Shadow DOM polyfill

<h1 align="center" style="border-bottom: none;">🔎 PerformanceObserver Polyfill</h1> <p align="center"> <a href="https://travis-ci.org/fastly/performance-observer-polyfill"> <img alt="Travis" src="https://img.shields.io/travis/fastly/performance-obs

ES6 Map Implemented in TypeScript

ARIA element reflection polyfill for strings

Polyfill for Function.prototype.bind

This fork provide the following on top of the original:

Polyfill for EventTarget options object support

HTML5 HTMLElement.dataset ponyfill

Development server for modern web apps

ES Proposal spec-compliant shim for Promise.withResolvers

An Event polyfill for legacy browsers.

Light-weight wrapper for the newer Promise-based MediaDevices.getUserMedia API with a fallback to navigator.getUserMedia (and it's prefixed variants)

A WebAssembly polyfill for the Barcode Detection API

An ESnext spec-compliant `Set.prototype.union` shim/polyfill/replacement that works as far down as ES3

A Laravel Mix extension to include polyfills by using Babel, core-js, and regenerator-runtime

WebAssembly interpreter

Ponyfill for React 16's <React.Fragment> component

EyeDropper API Polyfill

[![github actions][actions-image]][actions-url] [![coverage][codecov-image]][codecov-url] [![dependency status][deps-svg]][deps-url] [![dev dependency status][dev-deps-svg]][dev-deps-url] [![License][license-image]][license-url] [![Downloads][downloads-im

A polyfill for SVG's SVGPathSeg and SVGPathSegList

A robust & optimized `Array.from` polyfill, based on the ECMAScript 6 specification.

Polyfills for various EcmaScript 5 and EcmaScript 6 methods distributed as CommonJS modules that can be require'd individually or as a whole.

Ease adding polyfills to Nuxt.js projects using Polyfill.io among others

Array#forEach ponyfill for older browsers

This is a polyfill for TextEncoderStream.

No-bullshit super-simple es7 collections shim for Array#includes, Object.values, Object.entries

Element#classList for older browsers.

small zero dependent polyfill for `Object.groupBy` and `Map.groupBy`

A lightweight implementation of the Unicode Text Segmentation (UAX #29)

An ES spec-compliant `Array.prototype.push` shim/polyfill/replacement that works as far down as ES3.

WeakSet for IE11 and engines with a WeakMap

A minimal and dependency-free vanilla JavaScript datalist polyfill. Supports all standard's functionality as well as mimics other browsers behavior.

ES spec-compliant `Array.prototype.slice` shim/polyfill/replacement that works as far down as ES3

Lightweight polyfill/ponyfill for the Compression Streams API

JavaScript polyfills

A simple polyfill implementation of W3C's JavaScript Fullscreen API spec. Don't worry about the vendor specific Fullscreen API.

Polyfills for TextEncoder/TextDecoder

A CustomEvent polyfill for legacy browsers.

A screen.orientation ponyfill 🖥

Karma plugin for testing with es modules

An is-array polyfill for legacy browsers.

Babel 6 polyfill for IE<=10

Automatically adds datepickers to input[type=date] on IE, Firefox, and OS X Safari.

Fetch the current file and directory path, no matter your environment (Deno, Node.js, Web Browsers, ESM, CJS)

An ES-spec-compliant (proposed) String.prototype.at shim/polyfill/replacement that works as far down as ES3

Loosely test a package's compliance with the es-shim API

Cross-browser JavaScript shim that fully implements element.classList (referenced on MDN)

A shim for the iFrame "srcdoc" attribute

An ES spec-compliant `String.prototype.split` shim/polyfill/replacement that works as far down as ES3

WebGL2 API Polyfills for WebGL1 WebGLRenderingContext

A feature detected fix for non unique template literals

Polyfill for Node core `events.once

Polyfill for HTML 5 Canvas features.

A cross-browser ponyfill for File with a working constructor

Custom Properties polyfill for IE11.

Polyfill for window.location.origin

ES spec-compliant `Array.prototype.join` shim/polyfill/replacement that works as far down as ES3.

An essential Map poorlyfill for legacy browsers.

Polyfill for Crypto instance methods of Web Crypto API

A simple polyfill for IE8 and 9 that populates the value when empty

Polyfilled smooth scrolling behavior and helper function for Gatsby sites.

Essential WeakSet for legacy browsers.

All polyfills suggested by the Angular team

A simple SDP interoperability layer for Unified Plan/Plan B

A window.resizeTo polyfill for test environments like Jest & JSDOM

importModule() is a polyfill of import().

ES spec-compliant String.prototype.padStart shim.