Format, check, and read JSON data easily. It is completely free and very easy to use.
Loading tool...
Learn how to read, fix, and use JSON data for your coding projects.
A standard text format used to store and send data between computers and websites.
The JSON Toolkit is a free tool that helps you format, check, and clean up your JSON data. It runs entirely in your browser, meaning it is very fast and completely private.
This tool uses your browser’s native JSON parser to check for errors like missing commas or broken brackets. Your data never leaves your computer, making it safe for sensitive API keys.
{"name":"John","age":30,"city":"New York"}{
"name": "John",
"age": 30,
"city": "New York"
}The tool adds spaces and line breaks so the JSON is easy to read.
No strict limits. Because it runs 100% locally in your browser, you can format multi-megabyte JSON files instantly without waiting for a server response.
Yes. Trailing commas are strictly prohibited in the official JSON specification. The toolkit will flag them as invalid syntax immediately.
Yes. Your sensitive data, including API keys or personal information inside the JSON, is never transmitted to our servers. It stays securely on your device.