# Browserslist [![Cult Of Martians][cult-img]][cult] Browserslist logo by Anton Lovchikov The config to share target browsers and Node.js versions between different front-end tools. It is used in: * [Autoprefixer] * [Babel] * [postcss-preset-env] * [eslint-plugin-compat] * [stylelint-no-unsupported-browser-features] * [postcss-normalize] * [obsolete-webpack-plugin] All tools will find target browsers automatically, when you add the following to `package.json`: ```js "browserslist": [ "last 1 version", "> 1%", "maintained node versions", "not dead" ] ``` Or in `.browserslistrc` config: ```yaml # Browsers that we support last 1 version > 1% maintained node versions not dead ``` Developers set versions list in queries like `last 2 version` to be free from updating versions manually. Browserslist will use [Can I Use] data for this queries. Browserslist will take queries from tool option, `browserslist` config, `.browserslistrc` config, `browserslist` section in `package.json` or environment variables. [Browserslist Example] shows how every tool uses Browserslist. [cult-img]: https://cultofmartians.com/assets/badges/badge.svg [cult]: https://cultofmartians.com/done.html Sponsored by Evil Martians [stylelint-no-unsupported-browser-features]: https://github.com/ismay/stylelint-no-unsupported-browser-features [eslint-plugin-compat]: https://github.com/amilajack/eslint-plugin-compat [Browserslist Example]: https://github.com/browserslist/browserslist-example [postcss-preset-env]: https://github.com/jonathantneal/postcss-preset-env [postcss-normalize]: https://github.com/jonathantneal/postcss-normalize [Autoprefixer]: https://github.com/postcss/autoprefixer [Can I Use]: https://caniuse.com/ [Babel]: https://github.com/babel/babel/tree/master/packages/babel-preset-env [obsolete-webpack-plugin]: https://github.com/ElemeFE/obsolete-webpack-plugin ## Table of Contents 1. [Tools](#tools) 2. [Best Practices](#best-practices) 3. [Queries](#queries) 4. [Config File](#config-file) 5. [Shareable Configs](#shareable-configs) 6. [Configuring for Different Environments](#configuring-for-different-environments) 7. [Custom Usage Data](#custom-usage-data) 8. [JS API](#js-api) 9. [Environment Variables](#environment-variables) 10. [Cache](#cache) ## Tools * [`browserslist-ga`] and [`browserslist-ga-export`] download your website browsers statistics to use it in `> 0.5% in my stats` query. * [`browserslist-useragent-regexp`] compiles Browserslist query to a RegExp to test browser useragent. * [`browserslist-useragent-ruby`] is a Ruby library to checks browser by user agent string to match Browserslist. * [`browserslist-browserstack`] runs BrowserStack tests for all browsers in Browserslist config. * [`caniuse-api`] returns browsers which support some specific feature. * Run `npx browserslist` in your project directory to see project’s target browsers. This CLI tool is built-in and available in any project with Autoprefixer. [`browserslist-useragent-regexp`]: https://github.com/browserslist/browserslist-useragent-regexp [`browserslist-useragent-ruby`]: https://github.com/browserslist/browserslist-useragent-ruby [`browserslist-browserstack`]: https://github.com/xeroxinteractive/browserslist-browserstack [`browserslist-ga-export`]: https://github.com/browserslist/browserslist-ga-export [`browserslist-useragent`]: https://github.com/pastelsky/browserslist-useragent [`browserslist-ga`]: https://github.com/browserslist/browserslist-ga [`caniuse-api`]: https://github.com/Nyalab/caniuse-api ## Best Practices * Select browsers directly (`last 2 Chrome versions`) only if you are making a web app for a kiosk with one browser. There are a lot of browsers on the market. If you are making general web app you should respect browsers diversity. * There is a `defaults` query, which gives a reasonable configuration for most users: ```json "browserslist": [ "defaults" ] ``` * If you want to change the default set of browsers we recommend to combine `last 1 version`, `not dead` with `> 0.2%` (or `> 1% in US`, `> 1% in my stats`). `last n versions` adds too many dead browsers and does not add popular old versions. Choosing a percentage above `0.2%` will in the long run make popular browsers even more popular. We might run into a monopoly and stagnation situation, as we had with Internet Explorer 6. Please use this setting with caution. * Don’t remove browsers just because you don’t know them. Opera Mini has 100 million users in Africa and it is more popular in the global market than Microsoft Edge. Chinese QQ Browsers has more market share than Firefox and desktop Safari combined. ## Queries Browserslist will use browsers and Node.js versions query from one of these sources: 1. `browserslist` key in `package.json` file in current or parent directories. **We recommend this way.** 2. `.browserslistrc` config file in current or parent directories. 3. `browserslist` config file in current or parent directories. 4. `BROWSERSLIST` environment variable. 5. If the above methods did not produce a valid result Browserslist will use defaults: `> 0.5%, last 2 versions, Firefox ESR, not dead`. ### Query Composition An `or` combiner can use the keyword `or` as well as `,`. `last 1 version or > 1%` is equal to `last 1 version, > 1%`. `and` query combinations are also supported to perform an intersection of the previous query: `last 1 version and > 1%`. There is 3 different ways to combine queries as depicted below. First you start with a single query and then we combine the queries to get our final list. Obviously you can *not* start with a `not` combiner, since there is no left-hand side query to combine it with. | Query combiner type | Illustration | Example | | ------------------- | :----------: | ------- | |`or`/`,` combiner
(union) | ![Union of queries](img/union.svg) | `> .5% or last 2 versions`
`> .5%, last 2 versions` | | `and` combiner
(intersection) | ![intersection of queries](img/intersection.svg) | `> .5% and last 2 versions` | | `not` combiner
(relative complement) | ![Relative complement of queries](img/complement.svg) | `> .5% and not last 2 versions`
`> .5% or not last 2 versions`
`> .5%, not last 2 versions` | _A quick way to test your query is to do `npx browserslist '> 0.5%, not IE 11'` in your terminal._ ### Full List You can specify the browser and Node.js versions by queries (case insensitive): * `> 5%`: browsers versions selected by global usage statistics. `>=`, `<` and `<=` work too. * `> 5% in US`: uses USA usage statistics. It accepts [two-letter country code]. * `> 5% in alt-AS`: uses Asia region usage statistics. List of all region codes can be found at [`caniuse-lite/data/regions`]. * `> 5% in my stats`: uses [custom usage data]. * `cover 99.5%`: most popular browsers that provide coverage. * `cover 99.5% in US`: same as above, with [two-letter country code]. * `cover 99.5% in my stats`: uses [custom usage data]. * `maintained node versions`: all Node.js versions, which are [still maintained] by Node.js Foundation. * `node 10` and `node 10.4`: selects latest Node.js `10.x.x` or `10.4.x` release. * `current node`: Node.js version used by Browserslist right now. * `extends browserslist-config-mycompany`: take queries from `browserslist-config-mycompany` npm package. * `ie 6-8`: selects an inclusive range of versions. * `Firefox > 20`: versions of Firefox newer than 20. `>=`, `<` and `<=` work too. It also works with Node.js. * `iOS 7`: the iOS browser version 7 directly. * `Firefox ESR`: the latest [Firefox ESR] version. * `PhantomJS 2.1` and `PhantomJS 1.9`: selects Safari versions similar to PhantomJS runtime. * `unreleased versions` or `unreleased Chrome versions`: alpha and beta versions. * `last 2 major versions` or `last 2 iOS major versions`: all minor/patch releases of last 2 major versions. * `since 2015` or `last 2 years`: all versions released since year 2015 (also `since 2015-03` and `since 2015-03-10`). * `dead`: browsers without official support or updates for 24 months. Right now it is `IE 10`, `IE_Mob 10`, `BlackBerry 10`, `BlackBerry 7`, `Samsung 4` and `OperaMobile 12.1`. * `last 2 versions`: the last 2 versions for *each* browser. * `last 2 Chrome versions`: the last 2 versions of Chrome browser. * `defaults`: Browserslist’s default browsers (`> 0.5%, last 2 versions, Firefox ESR, not dead`). * `not ie <= 8`: exclude browsers selected by previous queries. You can add `not ` to any query. [`caniuse-lite/data/regions`]: https://github.com/ben-eb/caniuse-lite/tree/master/data/regions [two-letter country code]: https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Officially_assigned_code_elements [custom usage data]: #custom-usage-data [still maintained]: https://github.com/nodejs/Release [Can I Use]: https://caniuse.com/ ### Debug Run `npx browserslist` in project directory to see what browsers was selected by your queries. ```sh $ npx browserslist and_chr 61 and_ff 56 and_qq 1.2 and_uc 11.4 android 56 baidu 7.12 bb 10 chrome 62 edge 16 firefox 56 ios_saf 11 opera 48 safari 11 samsung 5 ``` ### Browsers Names are case insensitive: * `Android` for Android WebView. * `Baidu` for Baidu Browser. * `BlackBerry` or `bb` for Blackberry browser. * `Chrome` for Google Chrome. * `ChromeAndroid` or `and_chr` for Chrome for Android * `Edge` for Microsoft Edge. * `Electron` for Electron framework. It will be converted to Chrome version. * `Explorer` or `ie` for Internet Explorer. * `ExplorerMobile` or `ie_mob` for Internet Explorer Mobile. * `Firefox` or `ff` for Mozilla Firefox. * `FirefoxAndroid` or `and_ff` for Firefox for Android. * `iOS` or `ios_saf` for iOS Safari. * `Node` for Node.js. * `Opera` for Opera. * `OperaMini` or `op_mini` for Opera Mini. * `OperaMobile` or `op_mob` for Opera Mobile. * `QQAndroid` or `and_qq` for QQ Browser for Android. * `Safari` for desktop Safari. * `Samsung` for Samsung Internet. * `UCAndroid` or `and_uc` for UC Browser for Android. * `kaios` for KaiOS Browser. ## Config File ### `package.json` If you want to reduce config files in project root, you can specify browsers in `package.json` with `browserslist` key: ```json { "private": true, "dependencies": { "autoprefixer": "^6.5.4" }, "browserslist": [ "last 1 version", "> 1%", "IE 10" ] } ``` ### `.browserslistrc` Separated Browserslist config should be named `.browserslistrc` and have browsers queries split by a new line. Comments starts with `#` symbol: ```yaml # Browsers that we support last 1 version > 1% IE 10 # 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 in `BROWSERSLIST_CONFIG` environment variables. ## Shareable Configs You can use the following query to reference an exported Browserslist config from another package: ```json "browserslist": [ "extends browserslist-config-mycompany" ] ``` For security reasons, external configuration only supports packages that have the `browserslist-config-` prefix. npm scoped packages are also supported, by naming or prefixing the module with `@scope/browserslist-config`, such as `@scope/browserslist-config` or `@scope/browserslist-config-mycompany`. If you don’t accept Browserslist queries from users, you can disable the validation by using the `dangerousExtend` option: ```js browserslist(queries, { path, dangerousExtend: true }) ``` Because this uses `npm`'s resolution, you can also reference specific files in a package: ```json "browserslist": [ "extends browserslist-config-mycompany/desktop", "extends browserslist-config-mycompany/mobile" ] ``` When writing a shared Browserslist package, just export an array. `browserslist-config-mycompany/index.js`: ```js module.exports = [ 'last 1 version', '> 1%', 'ie 10' ] ``` ## Configuring for Different Environments You can also specify different browser queries for various environments. Browserslist will choose query according to `BROWSERSLIST_ENV` or `NODE_ENV` variables. If none of them is declared, Browserslist will firstly look for `production` queries and then use defaults. In `package.json`: ```js "browserslist": { "production": [ "> 1%", "ie 10" ], "modern": [ "last 1 chrome version", "last 1 firefox version" ], "ssr": [ "node 12" ] } ``` In `.browserslistrc` config: ```ini [production] > 1% ie 10 [modern] last 1 chrome version last 1 firefox version [ssr] node 12 ``` ## Custom Usage Data If you have a website, you can query against the usage statistics of your site. [`browserslist-ga`] will ask access to Google Analytics and then generate `browserslist-stats.json`: ``` npx browserslist-ga ``` Or you can use [`browserslist-ga-export`] to convert Google Analytics data without giving a password for Google account. You can generate usage statistics file by any other method. File format should be like: ```js { "ie": { "6": 0.01, "7": 0.4, "8": 1.5 }, "chrome": { … }, … } ``` Note that you can query against your custom usage data while also querying against global or regional data. For example, the query `> 1% in my stats, > 5% in US, 10%` is permitted. [`browserslist-ga-export`]: https://github.com/browserslist/browserslist-ga-export [`browserslist-ga`]: https://github.com/browserslist/browserslist-ga [Can I Use]: https://caniuse.com/ ## JS API ```js const browserslist = require('browserslist') // Your CSS/JS build tool code function process (source, opts) { const browsers = browserslist(opts.overrideBrowserslist, { stats: opts.stats, path: opts.file, env: opts.env }) // Your code to add features for selected browsers } ``` Queries can be a string `"> 1%, IE 10"` or an array `['> 1%', 'IE 10']`. 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. Options: * `path`: file or a directory path to look for config file. Default is `.`. * `env`: what environment section use from config. Default is `production`. * `stats`: custom usage statistics data. * `config`: path to config if you want to set it manually. * `ignoreUnknownVersions`: do not throw on direct query (like `ie 12`). Default is `false.` * `dangerousExtend`: Disable security checks for `extend` query. Default is `false.` * `mobileToDesktop`: Use desktop browsers if Can I Use doesn’t have data about this mobile version. For instance, Browserslist will return `chrome 20` on `and_chr 20` query (Can I Use has only data only about latest versions of mobile browsers). Default is `false`. For non-JS environment and debug purpose you can use CLI tool: ```sh browserslist "> 1%, IE 10" ``` You can get total users coverage for selected browsers by JS API: ```js browserslist.coverage(browserslist('> 1%')) //=> 81.4 ``` ```js browserslist.coverage(browserslist('> 1% in US'), 'US') //=> 83.1 ``` ```js browserslist.coverage(browserslist('> 1% in my stats'), 'my stats') //=> 83.1 ``` ```js browserslist.coverage(browserslist('> 1% in my stats', { stats }), stats) //=> 82.2 ``` Or by CLI: ```sh $ browserslist --coverage "> 1%" These browsers account for 81.4% of all users globally ``` ```sh $ browserslist --coverage=US "> 1% in US" These browsers account for 83.1% of all users in the US ``` ```sh $ browserslist --coverage "> 1% in my stats" These browsers account for 83.1% of all users in custom statistics ``` ```sh $ browserslist --coverage "> 1% in my stats" --stats=./stats.json These browsers account for 83.1% of all users in custom statistics ``` ## Environment Variables If some tool use Browserslist inside, you can change browsers settings by [environment variables]: * `BROWSERSLIST` with browsers queries. ```sh BROWSERSLIST="> 5%" gulp css ``` * `BROWSERSLIST_CONFIG` with path to config file. ```sh BROWSERSLIST_CONFIG=./config/browserslist gulp css ``` * `BROWSERSLIST_ENV` with environments string. ```sh BROWSERSLIST_ENV="development" gulp css ``` * `BROWSERSLIST_STATS` with path to the custom usage data for `> 1% in my stats` query. ```sh BROWSERSLIST_STATS=./config/usage_data.json gulp css ``` * `BROWSERSLIST_DISABLE_CACHE` if you want to disable config reading cache. ```sh BROWSERSLIST_DISABLE_CACHE=1 gulp css ``` [environment variables]: https://en.wikipedia.org/wiki/Environment_variable ## Cache Browserslist caches the configuration it reads from `package.json` and `browserslist` files, as well as knowledge about the existence of files, for the duration of the hosting process. To clear these caches, use: ```js browserslist.clearCaches() ``` To disable the caching altogether, set the `BROWSERSLIST_DISABLE_CACHE` environment variable. ## Security Contact To report a security vulnerability, please use the [Tidelift security contact]. Tidelift will coordinate the fix and disclosure. [Tidelift security contact]: https://tidelift.com/security