browserslist

What is browserslist?

The browserslist npm package is used to share target browsers and Node.js versions between different front-end tools, like Autoprefixer, Babel, and others. It utilizes a configuration file or package.json entries to specify the range of browser versions that your project supports. It helps in making decisions for transpiling JavaScript, adding vendor prefixes to CSS, and even defining which browser versions to test during the development process.

What are browserslist's main functionalities?

Defining target browsers

This feature allows you to define a range of browsers your project supports by specifying queries like market share, last versions, or excluding certain browsers. The code sample would typically be placed in a package.json file.

"browserslist": ["> 1%", "last 2 versions", "not dead"]

Integration with build tools

Browserslist can be integrated with build tools like Webpack, Babel, or PostCSS to automatically apply browser-specific transformations based on the defined browser support criteria.

const browserslist = require('browserslist');
const supportedBrowsers = browserslist('> 0.5%, last 2 versions, Firefox ESR, not dead');

CLI Usage

Browserslist provides a command-line interface (CLI) that can be used to check which browsers and versions are selected by your queries.

npx browserslist "> 1%, last 2 versions"

Configuring environments

You can define different sets of browsers for various environments, like production or development, within a .browserslistrc file.

[production]
> 1% in US
[development]
last 1 chrome version

Other packages similar to browserslist

caniuse-api

The caniuse-api provides raw browser support data from Can I Use, which is similar to the data that browserslist uses. However, it focuses more on querying specific features for browser support rather than defining a list of supported browsers for a project.

autoprefixer

Autoprefixer is a CSS post-processor that uses browserslist to add vendor prefixes to CSS rules. It is a consumer of browserslist data rather than a direct alternative, but it serves a similar purpose in terms of browser compatibility.

@babel/preset-env

Babel's preset-env is a smart preset that allows you to use the latest JavaScript without needing to micromanage which syntax transforms are needed by your target environment. It uses browserslist to determine which features need to be transformed or polyfilled. While not a direct alternative, it shares the goal of adapting code to be compatible with different environments.

README

Browserslist

Get browser versions that match given criteria. Useful for tools like Autoprefixer.

You can select browsers by passing a string. This library will use Can I Use data to return the appropriate list of all matching versions.

For example, the last version of each major browser and versions, with a usage of over 5% in global usage statistics:

browserslist('last 1 version, > 5%');
//=> ['and_chr 41', 'chrome 41', 'chrome 40', 'firefox 37', 'firefox 36',
//    'ie 11', 'ie_mob 11', 'ios_saf 8.1-8.3', 'opera 27', 'safari 8']

Browserslist will use browsers criterias from:

1. First argument.
2. BROWSERSLIST environment variable.
3. browserslist config file in current or parent directories.
4. If all methods will not give a result, Browserslist will use defaults:
   > 1%, last 2 versions, Firefox ESR, Opera 12.1.

Queries

You can specify the browsers by queries (case insensitive):

• last 2 versions: the last 2 versions for each major browser.
• last 2 Chrome versions: the last 2 versions of Chrome browser.
• > 5%: versions selected by global usage statistics.
• > 5% in US: uses USA usage statistics. It accepts two-letter country code.
• Firefox > 20: versions of Firefox newer than 20.
• Firefox >= 20: versions of Firefox newer than or equal to 20.
• Firefox < 20: versions of Firefox less than 20.
• Firefox <= 20: versions of Firefox less than or equal to 20.
• Firefox ESR: the latest [Firefox ESR] version.
• iOS 7: the iOS browser version 7 directly.

Blackberry and Android WebView will not be used in last n versions. You should add them by name.

Browsers

Names are case insensitive:

• Android for Android WebView.
• BlackBerry or bb for Blackberry browser.
• Chrome for Google Chrome.
• Firefox or ff for Mozilla Firefox.
• Explorer or ie for Internet Explorer.
• iOS or ios_saf for iOS Safari.
• Opera for Opera.
• Safari for desktop Safari.
• OperaMobile or op_mob for Opera Mobile.
• OperaMini or op_mini for Opera Mini.
• ChromeAndroid or and_chr for Chrome for Android (mostly same as common Chrome).
• FirefoxAndroid or and_ff for Firefox for Android.
• ExplorerMobile or ie_mob for Internet Explorer Mobile.

Usage

var browserslist = require('browserslist');

// Your CSS/JS build tool code
var process = function (css, opts) {
    var browsers = browserslist(opts.browsers, { path: opts.file });
    // Your code to add features for selected browsers
}

If a list is missing, Browserslist will look for a config file. You can provide a path option (that can be a file) to find the config file relatively to it.

Queries can be a string "> 5%, last 1 version" or an array ['> 5%', 'last 1 version'].

Config File

Browserslist’s config should be named browserslist and have browsers queries split by a new line. You can write a comment after #:

# Browsers that we support

> 1%
Last 2 versions
IE 8 # sorry

Changelog

0.3.3

• Fix DynJS compatibility (by Nick Howes).