README.md

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 list of all matching versions. For example, query to select all browser versions that are the last version of each major browser, or have a usage of over 10% in global usage statistics:

browserslist('last 1 version, > 10%');
//=> ["and_chr 47", "chrome 48", "chrome 47", "edge 13", "firefox 43",
//    "ie 11", "ie_mob 11", "ios_saf 9.0-9.2", "opera 34", "safari 9"]

Queries

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.

Multiple criteria are combined as a boolean OR. A browser version must match at least one of the criteria to be selected.

You can specify the versions 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.
• > 5% in my stats: uses custom usage data.
• ie 6-8: selects an inclusive range of versions.
• 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.
• not ie <= 8: exclude browsers selected before by previous queries. You can add not to any query.

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

Browserslist works with separated versions of browsers. You should avoid queries like Firefox > 0.

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.
• Edge for Microsoft Edge.
• 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.

Config File

Browserslist’s config should be named browserslist and have browsers queries split by a new line. Comments starts with # symbol:

# Browsers that we support

> 1%
Last 2 versions
IE 8 # sorry

Browserslist will check config in every directory in path. So, if tool process app/styles/main.css, you can put config to root, app/ or app/styles.

You can specify direct path to config by config option or BROWSERSLIST_CONFIG environment variables.

Environment Variables

If some tool use Browserslist inside, you can change browsers settings by environment variables:

• BROWSERSLIST with browsers queries.

  BROWSERSLIST="> 5%" gulp css

• BROWSERSLIST_CONFIG with path to config file.

  BROWSERSLIST_CONFIG=./config/browserslist gulp css

• BROWSERSLIST_STATS with path to the custom usage data.

  BROWSERSLIST_STATS=./config/usage_data.json gulp css

Custom Usage Data

If you have a website, you can query against the usage statistics of your site:

1. Import your Google Analytics data into Can I Use. Press Import… button in Settings page.

2. Open browser DevTools on [caniuse.com] add paste this snippet into Console:

   var e=document.createElement('a');e.setAttribute('href', 'data:text/plain;charset=utf-8,'+encodeURIComponent(JSON.stringify(JSON.parse(localStorage['usage-data-by-id'])[localStorage['config-primary_usage']])));e.setAttribute('download','stats.json');document.body.appendChild(e);e.click();document.body.removeChild(e);}

3. Save data to file in your project.

4. Give it to Browserslist by stats option or BROWSERSLIST_STATS environment variable:

   browserslist('> 5% in my stats', { stats: 'path/to/the/stats.json' });

Of course, you can generate usage statistics file by any other method. Option stats accepts path to file or data itself:

var custom = {
    ie: {
        6: 0.01,
        7: 0.4,
        8: 1.5
    },
    chrome: {
        …
    },
    …
};

browserslist('> 5% in my stats', { stats: custom });

Note that you can query against your custom usage data while also querying against global or regional data. For example, the query > 5% in my stats, > 1%, > 10% in US is permitted.

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
}

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

If a query 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.

For non-JS environment and debug purpose you can use CLI tool:

browserslist "> 1%, last 2 version"