Dev Tools

Format, validate and minify JSON in your browser — with the line, column and a plain-English reason when it will not parse.

Read the header and payload of a JSON Web Token, with its times explained. Decodes only — it does not verify the signature, and says so.

Test a regular expression against sample text, with every match highlighted and each capture group listed.

Generate UUID v4, v7 or v1, or Nano IDs — one or hundreds at a time, from your browser’s cryptographic random source.

Explain a cron expression in plain English and see when it will actually run next.

Generate title, description, canonical, Open Graph and Twitter Card tags for a page — with the mistakes that break social previews flagged before you copy them.

Build and send a real HTTP request — method, headers, query params and body — straight from your browser, and see the exact status, headers and body that came back.

Every HTTP status code from 100 to 511, in plain English, with what actually tends to cause each one.

The Tailwind CSS scales people look up most — spacing, breakpoints, font sizes, radius, z-index — plus common composed patterns, all searchable.