JSON Formatter & Validator
Paste minified or messy JSON below to instantly validate its syntax and format it into clean, readable, indented JSON. Useful for debugging API responses, config files, or log output. All formatting happens locally in your browser — your data is never sent anywhere.
Valid JSON ✓
Why validate and format JSON?
Minified JSON returned by APIs is efficient for transfer but hard for humans to read or debug. This tool parses your JSON to confirm it's syntactically valid, then re-prints it with 2-space indentation. Common errors it catches include trailing commas, unquoted keys, and mismatched brackets.
Common questions
Does this tool send my JSON to a server?
No — parsing and formatting happen entirely in your browser via JavaScript's built-in JSON parser.
Why does it say my JSON is invalid?
The error message includes the position where parsing failed — check for missing commas, unquoted keys, or a trailing comma before a closing bracket.
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