A fast, free JSON formatter and validator
Paste raw JSON on the left and our formatter instantly produces a beautified, syntax-highlighted version on the right — with line numbers, live validation and human-readable parse errors. Switch between 2-space, 4-space or tab indentation, minify back to a single line, copy to clipboard, or download as a .json file.
Everything runs locally in your browser. Your JSON is never uploaded or stored, so it's safe for sensitive payloads, API tokens, internal schemas and production data.
- Prettify and validate JSON
- Minify back to one line
- Syntax highlighting + line numbers
- Configurable indentation
- Copy, download, and upload
- 100% client-side & free