Browserslist Query Checker (caniuse / Autoprefixer)
Browserslist queries (> 1%, last 2 versions, not dead) determine which browsers your build tools target. Autoprefixer adds CSS vendor prefixes for them; Babel transpiles for them; ESLint flags features they don't support. This tool simulates how queries resolve.
How to use the Browserslist Query Checker (caniuse / Autoprefixer)
Type or paste a Browserslist query, or click an example chip. The result lists the browser versions the query resolves to today, each with its global usage share, so you can see exactly what your build tools will target.
What a Browserslist query controls
A single Browserslist query in your project quietly decides a lot: which CSS prefixes Autoprefixer adds, how far back Babel transpiles your JavaScript, and which features a linter warns about. Because the query resolves against live usage data, the same string can target a different set of browsers this year than it did last — so it is worth seeing what it actually resolves to rather than guessing from the syntax.
This evaluates a query the way your build does and lists the matching browser versions with their global usage share, turning an abstract string like > 1%, last 2 versions, not dead into a concrete list. Once you know your target browsers, set a matching JavaScript target in a tsconfig.json, and keep the source consistent with a .prettierrc config.
Common use cases
- Audit a target — see exactly which browsers a query includes before shipping.
- Trim bundle size — confirm that dropping old browsers actually removes transpilation weight.
- Debug prefixes — understand why Autoprefixer added, or skipped, a vendor prefix.
- Align the team — agree on one query and verify what it covers.
- Plan support — check a browser’s usage share before deciding to drop it.