How to use the JSON Validator
- Enter or paste your input in the tool above.
- Choose the available options and select Run tool or Process locally.
- Review, copy, or download the generated result.
What does the JSON Validator do?
The validator uses the browser JSON parser rather than pattern matching. It verifies objects, arrays, strings, numbers, booleans, and null according to JSON syntax and rejects common mistakes such as single quotes or trailing commas.
Common uses
- Validate request bodies before an API call
- Check configuration files during debugging
- Confirm copied JSON was not truncated
JSON Validator example
Example input
{"name":"Ada","skills":["math","code"]}Example output
✓ Valid JSONLimitations and important notes
- Syntax validation does not validate a business schema
- Duplicate object keys may be accepted with the last value winning
- JSON does not support comments, undefined, or NaN
Private browser-based processing
Your data is processed locally in your browser and is not uploaded or stored on our servers. Tool inputs are not saved to local storage.
JSON Validator features
- Free to use with no registration
- Fast client-side processing
- Clear validation and useful error messages
- Copy and download support
- Mobile-friendly accessible interface
Frequently asked questions
What is the difference between JSON validation and schema validation?
Syntax validation checks whether text is valid JSON. Schema validation also checks required fields, types, ranges, and domain rules.
Are single quotes valid in JSON?
No. JSON property names and string values must use double quotes.
Is the JSON Validator free to use?
Yes. The JSON Validator is completely free and requires no account or installation.
Is my data uploaded when using JSON Validator?
No. Your input and result are processed locally inside your browser and are not sent to our server.
Can I use JSON Validator on mobile?
Yes. The tool works in modern desktop and mobile browsers.