JSON Formatter & Validator
Format, minify and validate JSON in your browser, with the error position shown.
🔒 Runs in your browser. Nothing you enter is uploaded or stored.
How to use it
Paste JSON and press Format to indent it, or Minify to remove whitespace. If the JSON is invalid, the browser’s parser message tells you what went wrong and roughly where.
Common mistakes are trailing commas, single quotes instead of double quotes, and unquoted keys; all are invalid in standard JSON. Your data stays on your device, so it is safe for API responses that contain private details.
FAQ
Does it change my data?
Formatting only changes whitespace. Very large numbers beyond JavaScript's safe integer range (about 9 quadrillion) may lose precision when reformatted.
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