Get the code: check out, build, and run Chromium.

Chromium supports building on Windows, Mac and Linux host systems.

The process for building Chrome is generally the same on all platforms, but each platform has a few quirks. In order to keep you from having to jump all over the place, we have a self-contained page for each configuration you might want to build:

Android (Build on Linux)
Android Cast (Build on Linux)
Chrome OS (Build on Linux)
Fuchsia
iOS (Build on Mac)
Linux
Linux Cast
Mac
Windows