JSON Validator

Check JSON syntax and find parsing errors before using your data.

Local processing

Drop a file here, or paste your data. Maximum 10 MB. Text files must use UTF-8.

Ready when you are.

Your data is processed in your browser and is not stored on our servers.

JSON numbers use JavaScript precision. Quote large identifiers to preserve their digits. Duplicate object keys keep the last value.

What is JSON Validator?

Check JSON syntax and find parsing errors before using your data.

Validation checks syntax using the browser JSON parser. It does not validate a business schema or guarantee unique property names.

Why use JSON Validator?

Use this tool to inspect a small dataset or prepare data for another application without installing software. Processing takes place in this browser. No account is required.

How to use JSON Validator

  1. Paste your input, upload a file, or load Sample Data.
  2. Choose any applicable options and select Validate.
  3. Review the output, then copy or download it.

Example

Input

{"valid":true}

Output

Valid JSON.

Common problems

If parsing fails, correct the reported token and try again. Duplicate keys are accepted by JSON.parse and the last value wins. Large numeric identifiers should be strings.

Frequently asked questions

Is my conversion data uploaded?

No. Conversion inputs and outputs remain in this browser. Contact form messages are handled separately by WordPress.

Can I process large files?

The default limit is 10 MB. Browser memory and data complexity can impose lower practical limits.

Do I need an account?

No account is needed to use this tool.

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