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JSON Parser Online
Parse, validate and format JSON strings with detailed error reporting.
json
parser
validator
formatter
Formatting Options
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About JSON Parse Validator & Formatter
This free online JSON parse validator and formatter tool helps you validate, parse, and format JSON data using JavaScript's native JSON.parse() method. All processing happens in your browser for maximum privacy and security.
Features
- JSON Validation: Real-time validation using JavaScript's JSON.parse() method
- Auto-validation: Automatically validate JSON as you type
- Formatting Options: Pretty-print with customizable indentation or minify
- Error Detection: Detailed error messages for invalid JSON syntax
- Visual Feedback: Color-coded validation status with badges
- Copy & Download: Copy formatted JSON to clipboard or download as files
- Auto-save: Automatically saves your work for later sessions
- Privacy First: All processing happens locally in your browser
Validation Features
- Syntax Checking: Validates JSON syntax according to RFC 7159 standard
- Error Messages: Detailed error descriptions with line/column information
- Real-time Feedback: Instant validation as you type (optional)
- Manual Validation: On-demand validation with dedicated validate button
- Status Indicators: Visual badges showing valid/invalid status
Formatting Options
- Pretty Printing: Format JSON with proper indentation and line breaks
- Custom Indentation: Choose between 1-8 spaces for indentation
- Minification: Remove all unnecessary whitespace for compact output
- Consistent Formatting: Standardize JSON structure and spacing
Use Cases
- API Development: Validate JSON payloads and responses
- Configuration Files: Check JSON config files for syntax errors
- Data Processing: Ensure JSON data integrity before processing
- Debugging: Identify and fix JSON syntax issues
- Code Review: Format JSON for better readability
- Learning: Understand JSON structure and syntax rules
JSON Validation Rules
- Proper Quotes: Strings must use double quotes, not single quotes
- No Trailing Commas: Objects and arrays cannot have trailing commas
- Valid Data Types: Only string, number, boolean, null, object, and array
- Escaped Characters: Special characters must be properly escaped
- Balanced Brackets: All brackets and braces must be properly closed
Common JSON Errors
- Single Quotes: Use double quotes instead of single quotes for strings
- Unquoted Keys: Object keys must be enclosed in double quotes
- Trailing Commas: Remove commas after the last element in objects/arrays
- Undefined Values: Use null instead of undefined
- Comments: JSON doesn't support comments - remove them
Validation Tip
This tool uses JavaScript's native JSON.parse() method, which follows the strict JSON specification. Some JSON-like formats (like JavaScript object literals) may not be valid JSON and will show errors.
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