Why does valid-looking JSON fail?
Common causes include trailing commas, single quotes, unescaped line breaks, and missing double quotes.
JSON Validator - Check JSON Syntax Online
Validate JSON instantly, find syntax errors with line and column details, and keep your data private in the browser.
Input JSON
Formatted Result
View Mode:
Formatted code will be displayed here...
How to Use
- • Click "Beautify" to format and beautify JSON data
- • Click "Minify" to compress JSON data
- • Click "Validate" to check JSON syntax
- • Click "Load" to load sample data
- • Switch to "Tree View" to explore JSON structure interactively
- • Use the "History" button to save, view, and manage your past JSON entries locally.
- • All processing is done locally in your browser
How to validate JSON syntax
The validator uses the browser JSON parser and reports line and column details when available. Fix the first error and validate again; this is usually the fastest way to recover a valid document.
- Paste the JSON document.
- Select Validate and inspect the first error.
- Fix it and repeat until the document is valid.
Does validation modify the input?
No. Validation only reads the input and reports the result.