JSON Validator
Validate JSON data online. Catch syntax errors and verify JSON structure instantly.
- Instant
- 100% Private
- Free Forever
- No Signup
About This JSON Validator
Validate JSON online instantly. Paste any JSON string to check for syntax errors, trailing commas, missing quotes, and structural problems.
This free JSON validator runs locally in your browser — safe for private configs and API payloads.
What You Can Do
- Catch JSON syntax errors instantly
- Clear error messages for faster debugging
- Works as a lightweight JSON lint alternative
- Private browser-side validation
- No signup and no file uploads required
How to Use JSON Validator
- 1
Paste JSON
Paste the JSON you want to validate.
- 2
Validate
Run validation to check syntax and structure.
- 3
Fix issues
Use the error message to correct problems, then re-check.
Popular Use Cases
- Linting API responses before shipping
- Checking config files and manifests
- Teaching valid JSON syntax
Example
Invalid Input:
{
"name": "John"
"age": 30
}
Error: Expected comma or } at line 3Frequently Asked Questions
What does a JSON validator check?
It checks whether your text follows JSON syntax rules: quotes, commas, brackets, and value types.
Is validation private?
Yes. Validation happens in your browser. Your JSON is not uploaded to TinyToolbox servers.
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