Free JSON Formatter & Validator
Format, validate, and beautify JSON data instantly. Fix syntax errors, minify for production, or make complex JSON readable with proper indentation. No signup required.
100% free — no account needed
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Input JSON
0 chars
Formatted Output
Free JSON Formatter & Validator Features
Everything you need to work with JSON data efficiently
Copy & Download
One-click copy to clipboard or download as a .json file for your workflow.
Pretty Print
Beautify JSON with configurable indentation — choose 2 spaces, 4 spaces, 8 spaces, or tabs.
Minification
Compress JSON by removing whitespace for smaller payloads in production APIs.
Instant Validation
Get clear error messages pinpointing exactly where your JSON syntax breaks.
Frequently Asked Questions
What causes invalid JSON?
Common issues include trailing commas, single quotes instead of double quotes, missing quotes around property names, comments (not allowed in JSON), and undefined values.
What indent size should I use?
2 spaces is standard for web development and most JavaScript/TypeScript projects. 4 spaces is common for backend configuration files. Use tabs if your team prefers them.
Should I minify JSON in production?
Yes, for API responses and configuration served over the network. Minified JSON removes all unnecessary whitespace, reducing payload size significantly.
Is my data processed on a server?
No. All formatting and validation happens entirely in your browser. Your JSON data never leaves your device.
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