tree: 7292c23796c4e511cad882f81170f88faa8a3425 [path history] [tgz]
  1. front_end/
  2. scripts/
  3. services/
  4. .clang-format
  5. .devtools
  6. .eslintignore
  7. .eslintrc.js
  8. .gitignore
  9. .npmignore
  12. OWNERS
  13. package.json
  15. protocol.json

Chrome DevTools frontend

The client-side of the Chrome DevTools, including all JS & CSS to run the DevTools webapp.

It is available on NPM as the chrome-devtools-frontend package. It's not currently available via CJS or ES2015 modules, so consuming this package in other tools may require some effort.

Package versioning

The version number of the npm package (e.g. 1.0.373466) refers to the Chromium commit position of latest frontend git commit. It's incremented with every Chromium commit, however the package is updated roughly daily.

Source code

The frontend is available through a git subtree mirror on, with a regularly updating GitHub mirror at The codebase's true location is in third_party/WebKit/Source/devtools/ in Chromium's git repo.

Getting Started

  1. Clone the repo
  2. Go to repo root and run: npm start
    • This launches Chrome Canary and starts the dev server with 1 command
  3. Go to http://localhost:9222#custom=true&experiments=true

Power user tips:

You can customize the port for the dev server: e.g. PORT=8888 npm start.

You can also launch chrome and start the server separately:

  • npm run chrome
  • npm run server

When you start Chrome separately, you can pass extra args to Chrome:

npm run chrome --

(e.g. this launches Hacker News on startup)

If you want to reset your development profile for Chrome, pass in “--reset-profile”:

npm start -- --reset-profile


npm run chrome -- --reset-profile


Useful Commands


  • npm run format - formats your code using clang-format
  • npm test - builds devtools and runs all inspector layout tests

Note: If you're using a full chromium checkout and compiled content shell in out/Release, then npm test uses that. Otherwise, with only a front-end checkout (i.e. cloning from GitHub), then npm test will fetch a previously compiled content shell from the cloud (and cache it for future test runs).

Advanced testing:

  • npm test -- --fetch-content-shell - even if you‘re using a full chromium checkout and have a compiled content shell, this will fetch a pre-compiled content shell. This is useful if you haven’t compiled your content shell recently.
  • npm test -- -f --child-processes=16 - pass in additional flags to the test harness
  • npm test -- inspector/sources inspector/console - run specific tests
  • npm test -- inspector/cookie-resource-match.html --debug-devtools - debug a specific test (non-bundled & minified). You can use “-d” as a shorthand for “--debug-devtools”.
  • npm run test:build - only builds devtools (in debug mode)
  • npm run test:run - only runs devtools tests


Getting in touch