MDN Web Docs

🆕 Customize MDN's browser compat tables!

Press ⚙️ Settings on any compat table to choose which browsers and engines you see, and hide the ones you don't need.

Your picks are saved in your browser.

Try it 👇
developer.mozilla.org/en-US/docs/Web…

🆕 Introducing the MDN MCP server!

Bring MDN's docs and browser compat data straight into your AI agent or IDE for accurate, up-to-date answers about the web platform.

No more outdated guesses from training data.

Learn more 👇
developer.mozilla.org/en-US/blog/int…

Ever wish HTTP status codes were easier to remember? 🖼️

Check out this MDN cheatsheet that pairs each status code with an emoji to help you visualize what each one means, from 200 OK ✅ to 418 I’m a teapot 🫖

Check it out 👇

🦊 Firefox 150: web extensions can now use the Web Authentication API.

Extensions can create and retrieve WebAuthn credentials for any domain covered by their host permissions.

Read Now 👇
developer.mozilla.org/en-US/docs/Moz…

🦊 New in Firefox 150: the revert-rule CSS keyword.

Make a property behave as if the current rule didn't exist, letting a value from another matching rule take effect instead.

Read Now 👇
developer.mozilla.org/en-US/docs/Moz…