Fyrd/caniuse

caniuse is a community-maintained dataset and command-line tool that provides browser support information for HTML, CSS, and JavaScript features. At its core, it stores structured browser compatibility facts as a flat JSON dataset, keyed by feature identifiers and browser-version tuples, making the data easily queryable through a CLI or JSON API.

The project distinguishes itself through several practical tools built on top of this dataset. It includes a CSS compatibility linter that scans stylesheets to identify features lacking support in a target browser audience, and a feature support query tool that checks browser support from the command line without opening a browser. Users can also filter browser support data by configurable usage share thresholds to focus on relevant audience segments, and import custom usage analytics from external accounts to tailor compatibility data to specific audience patterns.

Beyond these core capabilities, caniuse supports community-driven curation through submissions and voting for updating or adding browser support information. It provides embeddable support table components for displaying compatibility data on external sites, and enables multi-feature cross-browser comparison to calculate the combined percentage of users who can use multiple features together. The project also integrates with cross-browser testing services for running website tests across thousands of real browser and device combinations.