JSON Formatter
Use this free JSON formatter to pretty-print, validate, minify, and recursively sort object keys entirely in your browser. Paste API responses, config files, or logs and get readable JSON with clear parse errors — nothing is sent to a server, so secrets in payloads stay on your device.
Runs entirely in your browser. Your data never leaves this device.
- Pretty-print and validate JSON
- Minify for compact payloads
- Recursive key sorting
- Client-side only — no uploads
- Copy formatted output in one click
How it works
- Paste or type JSON into the input panel.
- Click Format, Validate, Minify, or Sort keys — parsing happens in your browser with JSON.parse.
- Copy the output or clear and start over. Invalid JSON shows a clear error message.
Key features
- Pretty-print and validate JSON
- Minify for compact payloads
- Recursive key sorting
- Client-side only — no uploads
- Copy formatted output in one click
FAQ
Is my JSON uploaded to a server?
No. Parsing and formatting run entirely in your browser with JavaScript. Close the tab and the data is gone from this site.
Does Sort keys work on nested objects?
Yes. Keys are sorted recursively for objects and arrays are walked in order.
Why do I get a parse error?
JSON must be valid (double quotes, no trailing commas, no comments). The error message points to the issue.
Can I minify for production APIs?
Yes. Minify removes insignificant whitespace so payloads are compact for demos or size checks.
Is this better than an online JSON API?
For private payloads, yes — a client-side formatter avoids sending secrets to a remote pretty-printer.
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