# Stylelint [![npm version](https://img.shields.io/npm/v/stylelint)](https://www.npmjs.com/package/stylelint) [![Build Status](https://github.com/stylelint/stylelint/workflows/Testing/badge.svg)](https://github.com/stylelint/stylelint/actions/workflows/testing.yml?query=branch%3Amain) [![npm downloads](https://img.shields.io/npm/dm/stylelint)](https://npmcharts.com/compare/stylelint?minimal=true) A mighty, modern linter that helps you avoid errors and enforce conventions in your styles. ## Features It's mighty as it: - has over **170 built-in rules** for modern CSS syntax and features - supports **plugins** so you can create your own rules - automatically **fixes problems** where possible - is **well tested** with over 15000 unit tests - supports **shareable configs** that you can extend or create - is **unopinionated** so that you can customize it to your exact needs - **complements pretty printers** like Prettier - has a **growing community** and is used by Google, GitHub and WordPress And can be extended to: - parse **CSS-like syntaxes** like SCSS, Sass, Less and SugarSS - extract **embedded styles** from HTML, Markdown and CSS-in-JS object & template literals ## How it'll help you It'll help you **avoid errors**, for example: - invalid things, e.g. malformed hex colors and named grid areas - unknown things, e.g. units and functions that aren't in the CSS specs - valid things that are problematic, e.g. duplicated selectors and overridden properties And **enforce non-stylistic conventions**, for example: - what units, functions, at-rules etc are allowed - consistent patterns for selector names, at-rule names, custom properties etc - maximum specificity or maximum quantity of each selector type - your preferred notation for color functions, font weight etc There are also rules for enforcing stylistic conventions, but we now recommend you use Stylelint alongside a pretty printer like Prettier. Linters and pretty printers are complementary tools that work together. ## Example output ![Example](example.png) ## Guides - User guide - [Getting started](docs/user-guide/get-started.md) - [Configuration](docs/user-guide/configure.md) - [Rules](docs/user-guide/rules.md) - Usage - [CLI](docs/user-guide/usage/cli.md) - [Node.js API](docs/user-guide/usage/node-api.md) - [PostCSS plugin](docs/user-guide/usage/postcss-plugin.md) - [Options](docs/user-guide/usage/options.md) - Integrations - [Editor integrations](docs/user-guide/integrations/editor.md) - [Task runner integrations](docs/user-guide/integrations/task-runner.md) - [Other integrations](docs/user-guide/integrations/other.md) - [Ignoring code](docs/user-guide/ignore-code.md) - [Combining rules](docs/user-guide/combine.md) - [Using regex](docs/user-guide/regex.md) - [Errors & warnings](docs/user-guide/errors.md) - Developer guide - [Working on rules](docs/developer-guide/rules.md) - [Writing plugins](docs/developer-guide/plugins.md) - [Writing custom syntaxes](docs/developer-guide/syntaxes.md) - [Writing custom formatters](docs/developer-guide/formatters.md) - [Writing system tests](docs/developer-guide/system-tests.md) - [Writing processors](docs/developer-guide/processors.md) - Migration guide - [Migrating to 14.0.0](docs/migration-guide/to-14.md) - Maintainer guide - [Managing issues](docs/maintainer-guide/issues.md) - [Managing pull requests](docs/maintainer-guide/pull-requests.md) - [Performing releases](docs/maintainer-guide/releases.md) - About - [Vision](docs/about/vision.md) - [Semantic versioning](docs/about/semantic-versioning.md) ## Contributors Stylelint is maintained by volunteers. Without the code contributions from [all these fantastic people](https://github.com/stylelint/stylelint/graphs/contributors), Stylelint would not exist. [Become a contributor](CONTRIBUTING.md). ### Sponsors <object data="https://opencollective.com/stylelint/sponsors.svg?width=420&button=false" type="image/svg+xml"> <img src="https://opencollective.com/stylelint/sponsors.svg?width=840&button=false" /> </object> Thank you to all our sponsors! [Become a sponsor](https://opencollective.com/stylelint). ### Backers <object data="https://opencollective.com/stylelint/backers.svg?width=420&avatarHeight=48&button=false" type="image/svg+xml"> <img src="https://opencollective.com/stylelint/backers.svg?width=840&avatarHeight=48&button=false" /> </object> Thank you to all our backers! [Become a backer](https://opencollective.com/stylelint). ### Website hosting [![Deploys by Netlify](https://www.netlify.com/img/global/badges/netlify-color-accent.svg)](https://www.netlify.com) ## License [The MIT License](https://raw.githubusercontent.com/stylelint/stylelint/main/LICENSE).