JSON Formatter & Validator
Paste any JSON to instantly beautify it, minify it, or check it's valid — with a clear error message pointing to exactly what's wrong.
Your files are processed in your browser and never uploaded to any server.
How to use this tool
- 1Paste your JSON into the text box.
- 2Click Format / Beautify to pretty-print it, or Minify to compress it.
- 3Choose 2 spaces, 4 spaces, or tab indentation from the dropdown.
- 4If the JSON is invalid, the error message shows what's wrong.
- 5Click copy to copy the result to your clipboard.
Frequently asked questions
Is my JSON uploaded anywhere?+
No, everything is parsed and formatted locally in your browser.
Can it handle very large JSON files?+
Yes, though extremely large files may take a moment depending on your device.
Does it support JSON5 or comments?+
It follows strict JSON syntax; comments and trailing commas will be flagged as errors.
Malformed JSON is one of the most common sources of wasted debugging time for developers — a missing comma or an extra bracket can break an entire API response. This tool parses your JSON in real time and tells you immediately whether it's valid, and if not, exactly what the parser choked on. Use Beautify to turn a minified, hard-to-read blob into a properly indented structure with your choice of 2-space, 4-space, or tab indentation, or use Minify to strip all whitespace before sending JSON over the wire. Everything runs in your browser using the same JSON engine built into JavaScript, so nothing you paste — including API keys, tokens, or private config — is ever sent to a server.