JSON Validator
Validate and format JSON data. Check for syntax errors instantly.
What is JSON Validator?
A JSON validator checks if your JSON data is syntactically correct and properly formatted. It identifies errors like missing commas, unquoted keys, or mismatched brackets, and provides formatted output for valid JSON. All validation happens in your browser for speed and privacy.
How to Use This Tool
- Paste your JSON data in the input area
- Click 'Validate JSON' to check for errors
- Valid JSON will be formatted and displayed
- Invalid JSON will show a detailed error message
- Copy the formatted output for your project
Common Use Cases
- Debugging API responses with syntax errors
- Validating configuration files before deployment
- Checking JSON data from third-party sources
- Formatting minified JSON for readability
Frequently Asked Questions
What causes 'Unexpected token' errors in JSON?
Common causes include trailing commas after the last item, single quotes instead of double quotes, unquoted property names, or JavaScript-style comments which aren't allowed in JSON.
What's the difference between JSON and JavaScript objects?
JSON requires double quotes around keys and string values, doesn't allow trailing commas, and doesn't support comments, undefined, or function values. JavaScript objects are more flexible.
Is my JSON data sent to a server?
No, all validation happens locally in your browser using JavaScript's built-in JSON.parse(). Your data never leaves your device.