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How to Use the JSON Formatter & Validator

Paste JSON into the tool, and it validates the syntax instantly, reporting any error with its exact location — valid JSON can then be reformatted as pretty-printed (indented) or minified (compact) with a single action.

The JSON Formatter & Validator handles validation, pretty-printing, and minifying in one tool — here's how to use each function.

Validating JSON

Paste JSON in, and the tool immediately reports whether it's valid — if not, it typically points to the specific line and character where parsing failed, as covered in the guide on reading validation errors.

Switching between pretty-printed and minified

For valid JSON, switching between a readable, indented format and a compact, minified format takes one action — useful for moving between debugging (pretty-printed) and actual use in an application or API (often minified), as covered in the guide comparing the two formats.

Frequently asked questions

Is my JSON data sent to a server when I use this tool?

No — validation and formatting happen entirely in your browser using JavaScript running on your own device, so pasted JSON is never transmitted anywhere, which matters for anything containing sensitive data.

Can this tool fix invalid JSON automatically?

It identifies exactly where and why JSON is invalid, but fixing genuinely malformed JSON (missing commas, unmatched brackets) requires manual correction based on the reported error location, as covered in the error-reading guide.