Firefox Browser Developer Edition

Welcome to your new favourite browser. Get the latest features, fast performance, and the development tools you need to build for the open web.

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Firefox Privacy Notice

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Faster Performance

A Next-Generation CSS Engine

Firefox Quantum includes a new CSS engine, written in Rust, that has state-of-the-art innovations and is blazingly fast.

Design. Code. Test. Refine.

Build and Perfect your sites
with Firefox DevTools

Speak up

Feedback makes us better. Tell us how we can improve the browser and Developer tools.

Join the conversation

Get involved

Help build the last independent browser. Write code, fix bugs, make add-ons, and more.

Start now

Download the Firefox browser made for developers