Stylelint

A mighty CSS linter that helps you avoid errors and enforce conventions.

Features

It's mighty as it:

has over 100 built-in rules for modern CSS syntax and features
supports plugins so you can create your own custom rules
automatically fixes problems where possible
supports shareable configs that you can create or extend
can be customized to your exact needs
has 15k unit tests making it robust
is trusted by companies worldwide like Google and GitHub

And it can be extended to:

extract embedded styles from HTML, Markdown and CSS-in-JS template literals
parse CSS-like languages like SCSS, Sass, Less and SugarSS

How it'll help you

It'll help you avoid errors, for example:

invalid things, e.g. malformed grid areas
valid things that are problematic, e.g. duplicate selectors
unknown things, e.g. misspelled property names

And enforce conventions, for example:

disallow things, e.g. specific units
enforce naming patterns, e.g. for custom properties
set limits, e.g. the number of ID selectors
specify notations, e.g. for modern color functions

We recommend using a pretty printer like Prettier alongside Stylelint. Linters and pretty printers are complementary tools that work together to help you write consistent and error-free code.

Example output

Example

Guides

User guide
Developer guide
Migration guide
- Migrating to 15.0.0
- Migrating to 14.0.0
Maintainer guide
About
- Vision
- Semantic versioning

Contributors

Stylelint is maintained by volunteers. Without the code contributions from all these fantastic people, Stylelint would not exist. Become a contributor.