JSON Formatter & Validator
Format messy JSON beautifully, minify it, or validate it with one paste. Broken syntax gets flagged instantly so you can fix it - free, instant, and private, since everything runs in your browser.
Privacy note: Your JSON is parsed only in your browser — it is never uploaded or stored anywhere.
How to use
- Paste your JSON into the input box (or click Load Sample JSON to try it out).
- Click Format to pretty-print it, Minify to compress it, or Validate to only check it.
- If the JSON is valid you will see a green confirmation with key count and size stats; if not, the exact parser error is shown in red.
- Copy the output or download it as a .json file.
Tips
- Paste API responses here first when debugging - formatting reveals structure that one-line JSON hides.
- Watch for the two classic errors: trailing commas and unquoted keys.
- Minify before pasting JSON into URLs or size-limited fields.
- Your data never leaves the browser, so pasting API keys in test payloads stays local.
Frequently Asked Questions (FAQ)
What does the JSON Formatter do?
Paste messy JSON to format it beautifully, minify it, or just check that it is valid - free, instant and private.
Does it validate JSON?
Yes - it checks whether your JSON is valid and shows clear error messages when it is not.
Is my data private?
Yes - everything runs in your browser; nothing is uploaded.
What output options does it have?
Format with your chosen indent size, minify to one line, validate without changing anything, then copy the output or download it as a .json file.