What is JSON Formatter & Validator?
A JSON formatter takes raw, minified, or messy JSON and adds proper indentation, line breaks, and syntax highlighting so it is readable. It also validates JSON syntax to catch errors like missing commas or unmatched brackets. This tool runs in your browser — no data is uploaded.
Best for
- API responses
- Config files
- Nested object review
Privacy
JSON payloads stay in the browser, which is useful for confidential examples and production-adjacent data.
Quick tips
- Pretty-print before reviewing nested data.
- Sort keys when comparing payloads.
- Minify only after validation passes.
How to use this tool
- Paste raw JSON.
- Format, minify, or sort keys.
- Fix validation errors or copy the clean output.
Common questions
Does the JSON Formatter validate syntax?
Yes. It reports invalid JSON so you can fix the input before copying output.
Can I format private API responses?
Yes. Formatting happens locally in the browser.
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