Mello
{} Developer

JSON Formatter & Validator

Paste JSON to format, validate, or minify — runs entirely in your browser.

Runs in your browserNo account requiredNo uploadFree
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About JSON Formatter & Validator

Paste any JSON document and instantly format it with consistent indentation, validate that it parses, or minify it to a single line for transport.

Everything runs in your browser — your data is never sent to a server. Safe for sensitive payloads like API responses, secrets, and configs.

Frequently asked questions

No. All parsing happens locally using the browser's JSON parser.

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