Can I use

Type caniuse (or ciu) and the name of a web feature, such as grid, flexbox gap, webp or fetch. A panel shows which browsers support it, and since when.

What you see

• Up to eight matches as buttons, best first. Click one to switch. Words are matched against feature names, keywords and descriptions, and every word must match.
• Global support: the share of users whose browser fully supports the feature, and the share with partial support, as a bar.
• A table for Chrome, Edge, Firefox, Safari, Safari on iOS, Chrome for Android, Samsung Internet and Opera: the current version, whether it is supported, partly supported (with a note), needs a prefix, is off by default or is not supported, and the version that first supported it.
• The specification status, notes, a link to the specification and other reading, Copy summary (a one-line summary you can paste into a pull request) and Open on caniuse.com.

Where the data comes from

The data is the public Can I use dataset (licensed CC BY 4.0), from the Fyrd/caniuse repository on GitHub.

• The first search downloads it (about 450 KB compressed) from raw.githubusercontent.com. Your browser does this, not the server.
• It is then kept in your browser’s cache and used for a week; after that it is refreshed. If you are offline, the saved copy is used and the panel says so.
• The cache needs a secure context, which localhost is. If you open Home Screen by a plain http:// address on your network, the data is downloaded again in each browser session.
• Nothing about what you search for is sent anywhere: the search runs in your browser on the downloaded data.

The data is not part of the program, so the program stays small. It is also a widget, Can I use.