Developer tools that run in your browser
Small things you reach for a few times a week. Every one of them runs entirely in this tab — no account, no upload, no server that could keep a copy of what you pasted.
- JSON formatterIndent and validate JSON, with the line and column of the first thing that is wrong.
- JWT decoderRead the header and claims of a JSON Web Token, and see whether it has expired.
- Base64 encoder & decoderConvert text to Base64 and back, in standard or URL-safe alphabet.
- Regex testerRun a JavaScript regular expression over sample text and see every match and group.
- Markdown previewWrite Markdown on the left and see it rendered on the right.