JSON Formatter
Format (beautify), minify, and validate JSON with clear error messages. Copy formatted output in one click. Runs locally in your browser.
Key Features
- json formatter
- json beautifier
- json minifier
- json validator
- format json
- minify json
Format, minify, and validate JSON
This free JSON formatter is designed for developers, analysts, and anyone working with APIs or configuration files. Paste JSON into the editor to validate it instantly. Then use the tool to format (beautify) the JSON for readability, or minify it to reduce size. All processing happens client-side in your browser for speed and privacy.
When to use each option
Format / beautify JSON
Use formatted JSON when humans need to read or review it—debugging API responses, code review diffs, configuration edits, and documentation. A consistent indentation style makes nested objects and arrays easier to scan.
Minify JSON
Minifying removes unnecessary whitespace to reduce file size. This is useful when you want smaller payloads, tighter storage, or a compact string for embedding in logs or test cases. Minified JSON is harder to read, so keep a formatted version for editing.
Validation and error messages
JSON must be strict: property names require double quotes, trailing commas are not allowed, and comments are invalid. If your input is not valid JSON, the validator shows an error message so you can quickly identify what needs to be fixed.
Copy formatted output
After formatting, use the copy button to copy the prettified JSON directly to your clipboard. This is ideal for pasting into editors, API clients, or support tickets without reformatting.
Privacy and performance
The formatter runs locally in your browser. Your JSON is not uploaded to our servers for processing. This approach keeps the tool fast and helps maintain a lightweight, mobile-friendly experience.
Frequently Asked Questions
Quick answers about how this tool works.
Does this JSON formatter run client-side only?
Yes. Formatting, minifying, and validation are done in your browser so it’s fast and your JSON stays on your device.
What’s the difference between formatting and minifying JSON?
Formatting adds indentation and line breaks to make JSON readable. Minifying removes whitespace to reduce size.
Why does my JSON fail validation?
Common issues include trailing commas, single quotes instead of double quotes, missing quotes on keys, or comments (which JSON doesn’t allow).
Can I copy the formatted output?
Yes. Use the “Copy formatted” button to copy prettified JSON to your clipboard.
Is my JSON uploaded to a server?
No. This tool runs locally in your browser and does not upload your JSON for processing.