JSON formatter
Validate, format and minify. Preserve number precision.
Result
Instructions, examples and limits
Format without changing your data
Paste JSON to format and validate it automatically. Choose Minify for compact output. Open a local JSON or text file, copy the result or download it. Formatting only changes whitespace outside strings: large integers, decimal notation, key order and duplicate keys are preserved. Duplicate keys are not resolved and can be ambiguous in downstream software.
Example: {"id":9223372036854775807,"name":"research"}. The ID remains exact after formatting. Comments, trailing commas and JavaScript object literals are not valid JSON.
Maximum 200,000 characters / 200 KB file. Pretty formatting is limited to 80 nesting levels. This is syntax validation, not JSON Schema or business-rule validation.
Privacy
Input and output are processed only in this browser tab and are not uploaded or saved automatically. Reloading or leaving clears the content; download your result before leaving. Anonymous page-view statistics still apply.