JSON Validator
Validate JSON syntax with exact error positions, line and column numbers.
About JSON Validator
Validate JSON syntax against the strict RFC 8259 specification. Identify syntax errors, unquoted keys, trailing commas, single quotes, and invalid escape characters with exact line and character positions.
How to use JSON Validator
Add your file
Choose a file or drag it onto the upload box. We check that the file type and size are supported.
Pick your options
Change the settings shown next to the file if you need to. The defaults work for most files.
Download the result
Click the main button, then download your new file. Check it before you share or submit it.
What it does
- ✓Real-time syntax parsing according to RFC 8259 standards
- ✓Pinpoint error reporting highlighting line, column, and unexpected token context
- ✓Visual success badge confirming valid, production-ready schema
- ✓Completely client-side validation ensures sensitive customer data never leaves your computer
When to use it
Validate configuration files before committing to version control to prevent build breaks.
Verify incoming webhook JSON structures from Stripe, GitHub, and third-party APIs.
Ensure structured data schemas match JSON standards before deploying to production.
Validate large JSON data sets before initiating database imports.
Tips
- •Standard JSON requires double quotes (`"key"`) for property names; single quotes (`'key'`) are invalid.
- •Trailing commas after the last array item or object property (e.g. `[1, 2, ]`) will trigger validation errors.
- •Use the JSON Formatter tool after validation to format clean, readable output.