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  5. JSON Validator

JSON Validator

Validate JSON syntax and check for errors

Related Tools

  • JSON Formatter - format valid JSON
  • JSON Beautifier - prettify after validation
  • JSON Schema Builder - define structure rules
  • YAML Validator - validate YAML files
  • XML Validator - validate XML
  • HTML Validator - validate HTML

Learn the Concepts

📖JSON

How to Use JSON Validator

  1. 1

    Paste your JSON

    Copy and paste the JSON you want to validate into the input field.

  2. 2

    Check validity

    See instant validation results showing if your JSON is valid or has errors.

  3. 3

    Fix errors

    Review error messages with line numbers to locate and fix issues in your JSON.

Frequently Asked Questions

Yes, the JSON Validator is completely free with no usage limits. Validate as much JSON as you need without any registration, subscriptions, or restrictions.

Yes, all validation happens entirely in your browser. Your JSON data never leaves your device and is never sent to any server, ensuring complete privacy for sensitive configuration files, API payloads, or any other JSON content.

The validator checks for proper JSON syntax including correct bracket matching, valid string escaping, proper use of commas and colons, valid data types, and adherence to the JSON specification. It catches common errors like trailing commas, single quotes, and unquoted keys.

When validation fails, the tool provides detailed error messages indicating what went wrong and where. Common fixes include adding missing brackets, removing trailing commas, using double quotes instead of single quotes, and properly escaping special characters in strings.

This tool validates JSON syntax. For validating JSON against a specific schema (like OpenAPI or custom schemas), check out our JSON Schema Builder tool which allows you to define and validate against custom JSON schemas.