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JSON Formatter & Validator
Pretty-print, minify and validate JSON — with clear error messages, all in your browser.
Next step: JSON to CSV Converter →
About the JSON Formatter
Pretty-prints, minifies and validates JSON with clear error messages — the fastest way to make a messy API response readable or shrink it for production. Runs locally in your browser.
What this tool checks
- Formats (indents) and minifies JSON
- Validates and pinpoints syntax errors
- Copy the result with one click
Frequently asked questions
Why won't my JSON validate?
Common culprits: trailing commas, single quotes instead of double, or unquoted keys — all invalid in strict JSON.
Is my data safe?
Yes — formatting happens in your browser; the JSON is never uploaded.
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