Format JSON Without Uploading — Validate & Prettify
JSON formatters are among the most commonly used developer tools. Pasting JSON into a hosted service may expose configuration data, API responses, or other sensitive payloads to a third party. This formatter uses the browser's native JSON.parse to validate and prettify your JSON entirely locally — nothing leaves your browser.
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JSON formatting and validation happen in your browser using the native JSON.parse API — your data is never sent to any server.
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JSON Formatter →
Free · No upload · No account required
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Frequently Asked Questions
- Does the formatter validate JSON?
- Yes. If the JSON is invalid, the tool shows a parse error message with the location of the issue.
- Can I choose the indentation style?
- You can select 2-space or 4-space indentation.
- Is there a size limit on the JSON I can format?
- No server limit applies. Very large JSON documents may be slower to process depending on your browser and device.