JSON Formatter & Validator
Format, beautify, and minify your JSON data.
Output
Formatted JSON will appear here...
About This Tool
The JSON Formatter and Validator is an indispensable tool for debugging API payloads. JSON (JavaScript Object Notation) is the standard data interchange format on the web. It's often minified (squashed into one line) to save bandwidth. This tool expands minified JSON into a readable tree structure, highlights syntax errors, and can re-minify it when needed.
When to Use
- When analyzing messy, unformatted JSON returned from an API.
- When validating if a JSON configuration file has correct syntax before deploying.
- Minifying JSON strings before saving them to a database to save space.
Practical Examples
Messy Input{"user":"admin","active":true,"roles":["read","write"]}
Formatted Output{
"user": "admin",
"active": true,
"roles": [
"read",
"write"
]
}
Common Mistakes to Avoid
- Using single quotes ('') instead of double quotes ("") for string values and keys. Standard JSON stringifies strictly with double quotes.
- Leaving trailing commas at the end of an array or object. Many strict parsers will fail on { "a": 1, }.
Frequently Asked Questions
Q. Is my JSON data sent to a server?A. No. All formatting and validation happens strictly in your browser using JavaScript. No data is uploaded.
Q. How do I spot syntax errors?A. If your JSON is invalid, clicking 'Format' will instantly outline the input box in red and show the specific parsing error message at the bottom.