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Document format · .json

JSON: what it’s for

JSON (JavaScript Object Notation) is the world's data-exchange format: APIs return it, configs store it, and apps pass it around. It is human-readable, supported by every language, and interchanges cleanly with CSV for flat, tabular data.

Strengths

  • Human-readable and editable in any text editor
  • Parsed natively by every major programming language
  • Our formatter validates, pretty-prints, and minifies JSON locally
  • Converts losslessly to CSV whenever the data is flat and tabular

Honest limits

  • Strict syntax: no comments, no trailing commas — one typo breaks parsing
  • All numbers are float64, so huge integers can lose precision
  • Very large files (tens of MB) parse in memory — browsers slow down past that
  • Deeply nested structures flatten awkwardly into CSV rows

Free JSON tools

Every tool runs in your browser — files never leave your device. Badges say exactly what each tool does with JSON.

JSON FAQs

How do I check if my JSON is valid?

Paste it into the JSON formatter — it validates locally and points at the exact error, then pretty-prints or minifies the fixed result.

Can I convert JSON to CSV?

Yes, when the data is flat (arrays of uniform objects). Nested objects and arrays do not map to rows cleanly — flatten them first or keep JSON.

How do I compare two JSON files?

The JSON diff checker highlights added, removed, and changed keys side by side, entirely in your browser.

Is my JSON data uploaded?

No. API keys and payloads stay in your browser — validation, viewing, and conversion never touch a server.