JSON Formatter & Validator
Beautify, validate and minify JSON with clear error messages.
Developer Tools Runs in your browser
What does a JSON formatter do?
Paste broken JSON and the parser error tells you where it failed; paste valid JSON and it comes back pretty-printed with 2-space, 4-space or tab indentation, or minified to a single line. Validation uses the browser’s own JSON parser, so anything that passes here parses in production JavaScript too. Handy for reading API responses that arrive as one endless line.
How to use the JSON Formatter
- 1 Paste raw or minified JSON into the editor.
- 2 Hit Format for readable indentation, or Minify to strip whitespace.
- 3 Fix any syntax problem the error message points to, then format again.
- 4 Copy the result back into your project.
What you can use it for
- Debugging API responses.
- Cleaning up minified configuration files.
- Validating JSON before pasting it into code.
- Shrinking JSON payloads for production.
Frequently asked questions
Does this validate JSON?
Yes. Input goes through JSON.parse, so validation matches what browsers and Node.js accept. The error message includes the parser’s own description of what went wrong and roughly where.
Can it minify as well as beautify?
Both directions. Format re-indents with your chosen style; Minify collapses everything to one line with zero whitespace, the form you’d ship in a payload.
Can I paste API responses that contain tokens?
Yes. Formatting is done by the page’s own JavaScript and no request is made, so a payload holding session tokens or customer records stays on your machine.
What indentation can I use?
Two spaces, four spaces or tabs. Match your codebase so a formatted file doesn’t create whitespace noise in your next diff.
Related tools
More Developer Tools
More tools like this:
All Developer Tools