JSON Formatter & Validator
Beautify, validate and minify JSON instantly in your browser.
Paste any JSON and get pretty-printed, validated output. Errors include the exact line and column. One click to minify, copy, or download. Everything runs locally — your data never leaves the page.
Common use cases
- Pretty-print API responses copied from browser DevTools or Postman
- Validate JSON config files (package.json, tsconfig.json) before committing
- Minify JSON for production payloads or tight HTTP request bodies
- Inspect JWT payloads, webhooks and Stripe event JSON during debugging
Frequently asked questions
Will my JSON be uploaded?▾
No — formatting and validation run entirely in your browser, so sensitive payloads never leave your machine.
Can it handle large JSON files?▾
Yes, comfortably up to several megabytes. Above that the browser's built-in JSON.parse may slow down regardless of the tool.
What does the validator check?▾
Strict RFC 8259 compliance — comments and trailing commas are reported as errors with the exact position.
Can I sort keys alphabetically?▾
Yes — toggle 'sort keys' to alphabetise object keys at every nesting level. This is helpful when diffing two JSON files for meaningful changes.
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