How to Format & Validate JSON (the fast way)
This takes 10 seconds — no installs, no signups.
- Go to ZZBOLT JSON Formatter.
- Paste your JSON into the box.
- Click Format to pretty-print, or Minify for compact output.
- If something breaks, the validator shows the error message and location.
- Click Copy to use it in your code or API request.
Common errors (and fixes)
- Use double quotes for keys/strings — JSON doesn’t allow single quotes.
- Remove trailing commas after the last item in arrays/objects.
- Validate with the tool to pinpoint the exact character causing issues.
Tip: Works offline. Your JSON never leaves your browser.
Want a guide on another tool? Request a note.