Free JSON Formatter & Validator
Paste messy or minified JSON to instantly pretty-print it, minify it, or validate it — with clear, useful error messages when something is wrong.
Use it in three simple steps.
Paste your JSON
Drop your raw JSON into the editor on the left.
Format, minify or validate
Choose the action you need — Format for readable indentation, Minify for a compact single line, or Validate to check it is correct.
Copy the result
Copy the formatted output straight to your clipboard for use elsewhere.
Built to be fast, private and free.
Every Fenbrix tool runs fully in your browser — nothing you enter is uploaded or stored on our servers.
Why use Fenbrix's JSON Formatter?
Minified API responses, config files and log payloads are hard to read as one long line. This formatter turns them into clean, indented JSON — or the reverse, compressing readable JSON into a compact single line for production use.
Because validation happens with the browser's own JSON parser, error messages point to the exact character position of the problem instead of a generic 'invalid JSON' message, which makes debugging faster.
Things people ask about this tool.
Common causes are trailing commas, missing quotes around keys, or unclosed brackets. The error message points to the position where parsing failed.
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