JSON Validator

What is JSON Validation?

JSON (JavaScript Object Notation) has strict syntax rules: keys must be in double quotes, strings must be double‑quoted, no trailing commas, and brackets must be properly matched. Even a small syntax error can break an application or API integration. JSON validation checks your JSON against these rules and identifies exactly where the problem is.

This tool validates your JSON and provides detailed error messages with line and column numbers when invalid. It helps you quickly fix formatting issues, missing commas, or incorrectly placed brackets.

All processing is done locally in your browser – your data never leaves your device.

How to Use

Step 1: Paste your JSON into the input area.
Step 2: Click "Validate JSON".
Step 3: If valid, you'll see a success message. If invalid, the tool shows the error message with line and column numbers.
Step 4: Copy the result using the "Copy Result" button.

Use this tool to debug JSON from API responses, config files, or any JSON data before using it in your application.

Examples

Valid JSON:
{"name":"John","age":30,"city":"New York"}
Result: ✅ Valid JSON

Invalid JSON (missing comma):
{"name":"John" "age":30}
Result: ❌ Unexpected string at position 15

Who Uses JSON Validators?

• API Developers – ensuring responses are valid.
• Data Engineers – validating JSON datasets.
• QA Engineers – testing API outputs.
• Web Developers – debugging frontend data.
• DevOps – checking config files.

Pro Tips

• Always validate JSON before using it in production code.
• Error messages include line and column numbers – use them to locate the exact issue.
• Common errors: missing commas between properties, trailing commas, and unclosed brackets.
• Use a formatter first if your JSON is minified, then validate.
• The copy button helps you save error reports for debugging.

Frequently Asked Questions