Is my JSON data sent to a server?

No. All formatting and validation happens entirely in your browser. Nothing is sent to any server.

What is the maximum JSON size I can format?

There is no hard limit; however, very large JSON files (10 MB+) may be slower depending on your device.

Can I use this to validate JSON syntax errors?

Yes. The formatter highlights syntax errors and shows the exact position of the issue.

JSON Formatter

Format, validate, and beautify JSON data with syntax highlighting.

v1.0.0Updated Jul 2026

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Where it runs

Your browser

Data retention

None — nothing is uploaded or stored

Maintained by

EasyTechLabs Engineering

How this works & your privacy

🔒 Nothing you paste, type, or drop is uploaded, stored, or logged. All processing happens in your browser and the data never leaves your device — close the tab and it is gone.

Your input is parsed with the browser's native JSON parser and re-serialised with your chosen indentation (2, 4, tab, or minified). Optional key-sorting produces canonical output. Invalid JSON is reported with the parser's message and, where the engine provides it, the line and column of the error.

Limitations

Formatting normalises whitespace and (optionally) key order; it never changes values, so numbers keep their exact JSON representation.
Extremely large documents (10 MB+) format in-browser and may be slower on low-powered devices.
Comments and trailing commas are not valid JSON and are reported as errors — this is a strict RFC 8259 parser, not JSON5.

Standards & references

Frequently Asked Questions

Sort keys

JSON input

Formatted JSON

Output appears here…

Examples

🔒 Runs entirely in your browser — nothing you paste, type, or drop is uploaded, stored, or logged.