Free JSON Formatter & Validator Online
Format, validate, and minify JSON instantly in your browser. Your data never leaves your device.
How to use
- 1
Paste your JSON
Paste raw or minified JSON into the input field.
- 2
Click Format
Hit the Format button to instantly prettify your JSON with proper indentation.
- 3
Copy the result
Copy the formatted output and use it wherever you need.
Why use this tool?
- Processes entirely in your browser - your JSON never leaves your device
- Validates JSON and shows clear error messages for invalid input
- Supports both formatting (prettify) and minification in one tool
- Handles deeply nested objects and large JSON files
Frequently asked questions
- Is my JSON data safe?
- Yes. The formatter runs entirely in your browser using JavaScript. No data is sent to any server.
- What JSON size can it handle?
- It handles JSON files up to several MB comfortably. Very large files (100MB+) may be slow depending on your device.
- Does it validate my JSON?
- Yes. If your JSON is invalid, the tool shows the exact error and line number.
- Can I minify JSON too?
- Yes. Use the Minify button to compress JSON into a single line, reducing file size.
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