JSON Validator

Check if your JSON is valid and get detailed error messages with line numbers. Fix syntax errors instantly.

What Is JSON Validation?

JSON validation is the process of checking whether a given string conforms to the JSON syntax specification. A valid JSON string must follow strict rules about data types, structure, and formatting.

JSON validation is essential for:

How to Validate JSON Online

  1. Paste your JSON into the input editor.
  2. Click "Validate" to check the syntax.
  3. If valid, you'll see a success message. If invalid, detailed error information appears.
  4. Fix any reported errors and validate again.

Frequently Asked Questions

What errors can be detected?

The validator detects common errors like missing commas, unquoted keys, trailing commas, mismatched brackets, and invalid data types.

What is the difference between validation and formatting?

Validation checks syntax correctness, while formatting modifies whitespace for readability. Both are often used together in development workflows.

Is this tool safe?

Absolutely. Processing happens 100% in your browser. Your data is never sent to any server.

Real-World Examples

JSON validation is used when writing API clients, editing configuration files like tsconfig.json, debugging webhook payloads, ensuring CI/CD pipeline configs are valid, and teaching JSON syntax to new developers.

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