mdn/browser-compat-data

What it does

Stores machine-readable browser compatibility data for thousands of web platform features — CSS properties, JavaScript APIs, HTML elements, HTTP headers, and more — as structured JSON. It is the canonical source that powers compat tables across the web.

Who is it for

Browser vendors maintaining accurate compat records, documentation authors building compat tables (MDN, CanIUse, DevDocs), and tool authors who need structured compat data as input. Also used by linters and build tools to warn about unsupported features.

Where to find it

github.com/mdn/browser-compat-data

The npm package @mdn/browser-compat-data is updated on every release and can be used programmatically.

Who is maintaining it

Mozilla leads the project with significant contributions from Open Web Docs and a broad community of volunteers. Anyone can file issues or submit pull requests to add or correct data.