JSON Validator Online
100% Client-SideValidate JSON online for free. Check JSON syntax, identify parsing errors, and troubleshoot invalid JSON with this simple browser-based JSON validator.
Introduction
This JSON validator checks whether your JSON follows the valid JSON syntax and helps you identify parsing errors. It runs entirely in your browser, ensuring your data remains private.
How to validate: Paste or upload your JSON in the editor above. The validation happens automatically as you type.
Results: If your JSON is valid, you'll see a green status banner indicating success. If invalid, the banner turns red and displays the error message with line and column numbers to help you locate the issue.
Troubleshooting: Use the error details (line, column, and message) to fix your JSON. The validator highlights the exact location of the syntax error in the error snippet below the status banner.
Validation vs. Formatting: This tool only validates JSON syntax and reports errors. It does not modify your input. For formatting or beautifying JSON, use the JSON Formatter tool.
Key Capabilities
Frequently Asked Questions
What does a JSON validator check?
A JSON validator checks your JSON against the official JSON specification, verifying proper syntax including quotes, brackets, commas, and data types.
Why is my JSON invalid?
Common JSON validation errors include trailing commas, unquoted keys, single quotes instead of double quotes, missing brackets, and invalid data types like NaN or undefined.
How can I fix JSON syntax errors?
Use the error details provided by the validator to locate and fix the issue. Common fixes: remove trailing commas, quote keys with double quotes, ensure proper bracket matching, and replace single quotes with double quotes.
What are common JSON syntax mistakes?
Common JSON syntax mistakes include trailing commas (after the last item in an array or object), unquoted keys, using single quotes instead of double quotes, missing brackets (like a missing '}' or ']'), and trying to use invalid values like NaN, undefined, or comments.
Does JSON validation change my data?
No, validating JSON only checks the syntax and reports errors. It does not modify your input data. Your JSON remains unchanged unless you manually edit it.
Is this JSON validator free?
Yes, this JSON validator is completely free to use. There are no hidden charges or premium features.
Can I validate a JSON file?
Yes, you can upload a JSON file using the 'Upload File' button. The validator supports .json and .txt file extensions.
Is my JSON data uploaded to a server?
No, all validation is performed client-side in your browser. Your JSON data is never sent to or stored on any server.