JSON Validator

Validate JSON syntax and check for errors. Get detailed error messages with line numbers and comprehensive structure analysis.

JSON Input(Paste your JSON here)

Validation Result

Click "Validate JSON" to check your JSON syntax

JSON Validator Tool

Why Validate JSON?

  • • Syntax Errors: Catch missing commas, brackets, or quotes
  • • Debug Issues: Identify parsing problems before deployment
  • • API Integration: Ensure data format compatibility
  • • Data Integrity: Verify structure meets requirements
  • • Error Prevention: Avoid runtime errors in applications
  • • Quality Assurance: Maintain data quality standards

Perfect For

  • • Developers: Validating API responses and requests
  • • QA Engineers: Testing data format compliance
  • • Data Analysts: Checking dataset integrity
  • • System Admins: Validating configuration files
  • • Students: Learning JSON syntax and structure
  • • DevOps: Verifying deployment configurations

Common JSON Errors

Syntax Errors

  • • Missing Comma: Between object properties or array items
  • • Trailing Comma: Extra comma after last item
  • • Unmatched Brackets: Missing opening or closing brackets
  • • Unquoted Keys: Object keys must be in quotes
  • • Invalid Values: Undefined, functions, or comments

Format Issues

  • • Single Quotes: JSON requires double quotes only
  • • Escape Characters: Unescaped quotes or backslashes
  • • Control Characters: Invalid characters in strings
  • • Number Format: Leading zeros or invalid number syntax
  • • Unicode Issues: Improperly escaped Unicode characters

Validation Examples

❌ Invalid JSON

{
  name: "John",          // No quotes on key
  'age': 30,             // Single quotes
  "skills": [
    "JavaScript",
    "Python",            // Trailing comma
  ],
  "active": true,
}

✅ Valid JSON

{
  "name": "John",
  "age": 30,
  "skills": [
    "JavaScript",
    "Python"
  ],
  "active": true
}

JSON Best Practices

Syntax Guidelines

  • • Double Quotes: Always use double quotes for strings
  • • No Trailing Commas: Remove commas after last items
  • • Proper Nesting: Ensure balanced brackets and braces
  • • Valid Values: Use only JSON-compliant data types
  • • Escape Characters: Properly escape quotes and backslashes

Structure Tips

  • • Consistent Keys: Use consistent naming conventions
  • • Reasonable Depth: Avoid excessive nesting levels
  • • Data Types: Choose appropriate types for values
  • • Documentation: Validate against schema when possible
  • • Testing: Always validate before using in production

Privacy & Security

Data Protection

  • • Client-Side Processing: All validation happens in your browser
  • • No Server Upload: Your JSON data never leaves your device
  • • No Storage: No data is saved or logged anywhere
  • • Secure Connection: HTTPS encryption for website access
  • • Privacy First: No tracking or analytics on sensitive data

Validation Features

  • • Real-time Validation: Instant error detection
  • • Detailed Errors: Specific error messages with context
  • • Structure Analysis: Comprehensive JSON analysis
  • • Line Numbers: Pinpoint exact error locations
  • • Cross-Platform: Works on all devices and browsers

Frequently Asked Questions

Why do I need to validate JSON before using it?
JSON validation prevents runtime errors in applications by catching syntax issues like missing commas, unmatched brackets, or invalid data types before your code tries to parse the data. This saves debugging time and prevents application crashes.
What are the most common JSON validation errors?
The most common errors are missing commas between properties, trailing commas after the last item, unquoted object keys, using single quotes instead of double quotes, and unmatched brackets or braces. Our validator provides specific error messages to help you identify and fix these issues.
Does the validator show error line numbers?
Yes, our validator attempts to identify the approximate line number where errors occur. This helps you quickly locate and fix syntax problems in large JSON files, making debugging much more efficient.
What does the structure analysis feature show?
For valid JSON, we provide a structure analysis showing the root data type (object/array), number of properties or items, nesting depth, and file size. This helps you understand your data's complexity and optimize it if needed.
Can I validate large JSON files safely?
Yes, validation happens entirely in your browser with no file size limits. Your data never leaves your device, ensuring privacy and security. Large files are processed efficiently using JavaScript's built-in JSON parser.
What's the difference between validation and formatting?
Validation checks if your JSON syntax is correct and can be parsed without errors. Formatting (prettifying) adds proper indentation and line breaks for readability. Use our JSON prettifier after validation to make your JSON more readable.