Skip to content
Back to Knowledge Base

Configuring Browser Support

Builds that use browserslist, such as @nx/rspack web builds, read your application's browser support from it. It decides which transformations run on your code in both production and development builds.

Vite doesn't read browserslist. Set build.target in your Vite config instead.

In general, the more modern your applications browser support is, the smaller the filesize as the code can rely on modern API's being present and not have to ship polyfills or shimmed code.

Nx generators don't create a browserslist config. To add one, use either of these options:

  • Create a .browserslistrc file in the project root.
  • Add a browserslist key to the project's package.json.

Browserslist also looks in parent directories, so a config in the workspace root applies to every project that doesn't have its own.

For example, the following .browserslistrc supports only recent browser versions.

last 1 Chrome version
last 1 Firefox version
last 2 Edge major versions
last 2 Safari major version
last 2 iOS major versions
Firefox ESR
not IE 9-11

This configuration is used for many tools including babel, autoprefixer, postcss, and more to decide which transforms are necessary on the source code when producing built code to run in the browser.

For additional information regarding the format and rule options, please see: https://github.com/browserslist/browserslist#queries

Debugging browser support

Section titled “Debugging browser support”

Sometimes broad configurations like > 0.5%, not IE 11 can lead to surprising results, due to supporting browsers like Opera Mini or Android UC browser.

To see what browsers your configuration is supporting, run npx browserslist in the application's directory to get an output of browsers and versions to support.

npx browserslist
chrome 154
edge 154
edge 153
firefox 157
firefox 153
ios_saf 27.0
ios_saf 26.6
ios_saf 26.5
ios_saf 26.4
ios_saf 26.3
ios_saf 26.2
ios_saf 26.1
ios_saf 26.0
safari 27
safari 26.6
safari 26.5
safari 26.4
safari 26.3
safari 26.2
safari 26.1
safari 26.0

Alternatively, if your support config is short you can just add it as a string param on the CLI:

Terminal window
npx browserslist '> 0.5%, not IE 11'

Last updated: