Beautify, validate, and minify JSON with syntax highlighting. Paste your JSON and get clean, readable output instantly.
JSON (JavaScript Object Notation) is a lightweight data-interchange format that's easy for humans to read and write, and easy for machines to parse and generate. It's the most common format for APIs, configuration files, and data storage in modern web development.
By default we use 2 spaces for indentation, which is the most common convention in JavaScript and web development.
There's no hard limit, but very large files (10MB+) may slow down your browser since all processing is local.
No. All formatting and validation happens entirely in your browser using JavaScript. We never see, store, or transmit your data.
Repair mode fixes common JSON errors especially from AI output: trailing commas, single quotes instead of double, unquoted object keys, JavaScript-style comments (// and /* */), and missing closing brackets. It can fix most malformed AI-generated JSON automatically.
Yes — it both beautifies and validates. Invalid JSON shows the exact error and position instead of silently failing.
Yes. Choose 2, 4 spaces or tabs, and minify mode compresses to a single line for storage or network transfer.
Yes. Formatting is fully reversible: paste minified JSON and click format to beautify; paste formatted JSON and click minify to compress.
No hard limit — everything runs locally in your browser, so even multi-megabyte JSON documents can be processed.
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