JSON Formatter & Validator

Paste JSON to format, validate, or minify — 100% client-side.

Paste JSON below

Input

Output

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Format, validate, and minify

Paste JSON and it gets pretty-printed with consistent indentation, or minified down to a single line if you need to paste it somewhere space-constrained (an environment variable, a config field, a curl command). If the JSON is invalid, it points out the error with a line number instead of leaving you to scan the whole payload manually.

When you actually need this

API responses logged to a terminal come back as one unreadable line. Config files hand-edited by someone else lose their formatting. A webhook payload from a third-party service arrives minified. This exists for exactly those moments, when you need to actually read the structure of a piece of JSON, not just look at it.