JSON Formatter and Validator
Validate, format, and minify JSON locally in your browser.
Validate, format, and minify strict JSON using your browser's native parser. This tool does not accept JSON5, JSONC, YAML, comments, trailing commas, or JavaScript object literals.
Formatting and minification change whitespace only, so key order, duplicate property names, string escapes, and number spellings stay intact. Parse errors report a one-based line and column when available. Processing stays in this browser—nothing is uploaded or saved.
Stable key sorting is not offered in v1. Duplicate names and IEEE-754 number precision limits are called out in the interactive panel after a successful operation.
Duplicate object names are accepted. Number text is preserved on format and minify.
0 code units · max 5,000,000
Strict JSON only (native browser parsing). Your JSON stays in this browser. It is not saved or uploaded.
Paste JSON, then Validate, Format, or Minify. Line and column follow the editor's UTF-16 positions.