JSON Validator
Validate JSON syntax in real time with line-by-line error detection and diagnostics.
Check JSON syntax against strict RFC 8259 specifications. Instantly detect syntax errors, unescaped quotes, trailing commas, and malformed arrays with precise error diagnostics and suggestions.
About JSON Validator & Linter
A single misplaced comma or unclosed bracket can crash an application or cause an API request to fail. JSON Validator gives engineers instant confirmation that data payloads are syntactically sound.
How to Use JSON Validator & Linter
- Enter JSON: Paste the JSON data you wish to validate.
- Automatic validation: Our validation engine checks syntax tokens in real time.
- Review status: See an instant green Valid badge or red error diagnostics banner.
- Correct and copy: Fix identified syntax issues and copy the valid JSON.
Key Features
- Strict RFC 8259 syntax validation
- Catches trailing commas & single quotes
- Real-time error message readout
- Safe browser memory validation
- Zero server uploads
Common Use Cases
- Verifying webhook payloads before sending requests in Postman or cURL.
- Checking configuration files before deploying code to production servers.
- Troubleshooting parsing exceptions in mobile and web applications.
Frequently Asked Questions
What are the most common JSON syntax errors?
The most frequent errors are trailing commas after the last array/object element, using single quotes instead of double quotes, and forgetting to quote object keys.
Are my confidential JSON records uploaded to any server?
No. All validation runs locally inside your browser using JavaScript error tracing.
Does this validator support comments in JSON (like JSONC)?
Standard RFC 8259 JSON strictly prohibits comments. This validator enforces official RFC specifications to ensure cross-platform compatibility.
Can this tool help identify the exact line number of a syntax error?
Yes, when a syntax error occurs, the validator provides the precise character position and detailed diagnostic message to help you fix it quickly.
Privacy Guarantee
Validation executes client-side. No data is stored or logged.
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