JSON formatter
Format or minify JSON while preserving numbers and key order.
Formatted result
Paste your JSON and click “Format JSON”.
Only whitespace and line breaks change. Numbers and key order are preserved. Your input is not sent or stored.
How to use JSON formatter
- 01Paste your JSON, up to 200 KB.
- 02Choose 2 or 4 spaces and format it, or click “Minify JSON”.
- 03Copy the result or save it as a JSON file. Syntax errors show a line and column.
About JSON formatter
Make JSON easier to read or remove unnecessary whitespace. Large integers, duplicate keys, number formatting and string contents are preserved. Inputs are not sent or saved.
What formatting changes and preserves
Formatting adds indentation and line breaks. Minifying removes unnecessary whitespace outside strings. Whitespace inside strings and escaped line breaks remain unchanged.
Large integers, trailing decimal zeros, exponential notation and duplicate keys keep their original form. Applications may handle duplicate keys differently. Validation checks JSON syntax, not the requirements of a particular API or configuration.
Generate UUIDs for JSON test dataFrequently asked questions
Are large numbers preserved?
Yes. Formatting changes whitespace rather than parsing numbers into JavaScript values, so large integers and original number notation remain intact.
Are comments or trailing commas allowed?
No. The tool validates strict JSON and reports syntax errors with their line and column.
Is my input stored or shared?
No. Processing happens locally, and this page does not load advertising or analytics scripts. The limit is 200 KB and 128 nesting levels.
Is it free to use?
Yes. All tools are free, with no account required.
