JSON Formatter & Validator Tool

Format, validate, and transform JSON documents with our free online tool. All processing happens in your browser.

JSON Input

Output


                                    

                                

                            

                        

                        

                            
                            
                            
                        

                    

                

            

        

        

        

            
Complete Guide to Using Our JSON Formatter & Validator Tool

            

                

                    

                        

                            
Formatting JSON

                        

                        

                            
    
                                
  1. 
                                    
     Paste your JSON into the input box: 
      
                                            
    • Works with valid JSON objects or arrays
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    • Handles nested structures of any depth
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    2. 
                                
  2.  Click "Beautify" to format your JSON: 
      
                                        
    • Adds proper indentation (2 spaces by default)
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    • Standardizes structure for readability
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    3. 
                                
  3.  Click "Minify" to compress your JSON: 
      
                                        
    • Removes all unnecessary whitespace
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    • Converts to single-line format
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    4. 
                                
  4. 
                                    
     Copy results with: 
      
                                            
    •  Copy button
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    • Standard Ctrl+C/Cmd+C
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    5. 
                            

                        

                    

                

                

                    

                        

                            
Validating JSON

                        

                        

                            
    
                                
  1. 
                                    Paste JSON content to validate (automatic validation)
                                
    2. 
                                
  2. 
                                    
    
                                        Error detection:
                                        
      
                                            
    • Invalid syntax is immediately flagged
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    • Precise error location (line and column)
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    • Suggested fixes for common mistakes
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    3. 
                                
  3. 
                                    Visual feedback:
                                    
      
                                        
    • Input field highlights when invalid
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    • Detailed error explanation appears
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    • Cursor jumps to error location
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    4. 
                                
  4. 
                                    Syntax highlighting in formatted output:
                                    
      
                                        
    • Keys, strings, numbers, booleans color-coded
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    • Improved readability of complex structures
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    5. 
                            

                        

                    

                

            

            

                
Common JSON Validation Errors & Solutions

                

                    
                    

                        
Error Type

                        
Example

                        
Solution

                        
Tool Assistance

                    

            
                    
                    

                        

                            Missing Quotes
                        

                        
{name: "value"}

                        

                            Add quotes: {"name": "value"}
                        

                        

                            Highlights unquoted property, suggests adding quotes
                        

                    

            
                    
                    

                        

                            Trailing Comma
                        

                        
{"a": 1, "b": 2,}

                        

                            Remove comma: {"a": 1, "b": 2}
                        

                        

                            Points to exact comma, suggests removal
                        

                    


                    
                    

                        

                            Unclosed Brace/Bracket
                        

                        
{"a": [1, 2}

                        

                            Add closing bracket: {"a": [1, 2]}
                        

                        

                            Shows expected closing character location
                        

                    


                    
                    

                        

                            Invalid Number
                        

                        
{"a": 01}

                        

                            Use valid number: {"a": 1} or string: {"a": "01"}
                        

                        

                            Highlights invalid number format, explains restriction
                        

                    

            
                    
                    

                        

                            Unescaped Character
                        

                        
{"text": "Line\nBreak"}

                        

                            Escape special characters: {"text": "Line\\nBreak"}
                        

                        

                            Identifies unescaped character, shows correct format
                        

                    

                

            

            

                
Detailed Usage Examples

                

                    

                        

                            
                        

                        

                            

                                
Beautifying minified JSON:

                                
    
                                    
  1. Paste minified JSON:
                                        {"name":"John","age":30,"cars":["Ford","BMW","Fiat"]}
    2. 
                                    
  2. Click Beautify
    3. 
                                    
  3. Result:
                                        { "name": "John", "age": 30, "cars": [ "Ford", "BMW", "Fiat" ] }
                                    
    4. 
                                


                                
Minifying formatted JSON:

                                
    
                                    
  1. Paste formatted JSON (like above example)
    2. 
                                    
  2. Click Minify
    3. 
                                    
  3. Result: {"name":"John","age":30,"cars":["Ford","BMW","Fiat"]}
    4. 
                                

                            

                        

                    


                    

                        

                            
                        

                        

                            

                                
Fixing common syntax errors:

                                
    
                                    
  1. Paste invalid JSON: {name: "John", age: 30}
    2. 
                                    
  2. Tool immediately shows error: "Property name must be in quotes"
    3. 
                                    
  3. Cursor jumps to first error location (name)
    4. 
                                    
  4. Add quotes to fix: {"name": "John", "age": 30}
    5. 
                                


                                
Identifying structural problems:

                                
    
                                    
  1. Paste JSON with missing bracket: {"items": [1, 2, 3}
    2. 
                                    
  2. Tool shows: "Expected ']' to close array"
    3. 
                                    
  3. Cursor positioned at opening [ character
    4. 
                                    
  4. Add missing bracket: {"items": [1, 2, 3]}
    5. 
                                

                            

                        

                    


                    

                        

                            
                        

                        

                            

                                
Working with nested structures:

                                
    
                                    
  1. Paste complex JSON:
                                        {"employees":[{"name":"John","skills":["JavaScript","HTML"]},{"name":"Sarah","skills":["Python","SQL"]}]}
                                    
    2. 
                                    
  2. Click Beautify
    3. 
                                    
  3. Formatted result:
                                        { "employees": [ { "name": "John", "skills": [ "JavaScript", "HTML" ] }, { "name": "Sarah", "skills": [ "Python", "SQL" ] } ] }
                                    
    4. 
                                

                            

                        

                    

                

            


            

                
Key Technical Details

                

                    

                        

                            

                                
JSON Specifications

                            

                            

                                
    
                                    
  • Data Types:
                                        
      
                                            
    • Strings (must be double-quoted)
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    • Numbers (no leading zeros)
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    • Booleans (true/false)
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    • Arrays (ordered lists)
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    • Objects (key-value pairs)
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    • null
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  • Syntax Rules:
                                        
      
                                            
    • Property names must be in double quotes
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    • No trailing commas in arrays/objects
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    • No comments allowed
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    • Strings must escape special characters
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Common Use Cases

                            

                            

                                
    
                                    
  • API communication: Request/response format
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  • Configuration files: App settings storage
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  • Data storage: NoSQL databases
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  • Data exchange: Between different systems
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  • Formatted JSON is great for:
                                        
      
                                            
    • Human-readable documentation
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    • Debugging and development
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    • Configuration files
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  • Minified JSON is great for:
                                        
      
                                            
    • Network transmission
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    • Storage efficiency
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    • Production environments
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Best Practices

                
    
                    
  • Always validate JSON from external sources
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  • Use formatted JSON during development for readability
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  • Minify JSON for production to reduce size
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  • Consistent formatting helps with version control
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  • For complex JSON:
                        
      
                            
    • Validate early and often during creation
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    • Use our tool to reformat before saving
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    • Consider using JSON Schema for validation
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Frequently Asked Questions

                

                

                    

                        

                            

                                
                            

                            

                                

                                    
Common reasons include:

                                    
    
                                        
  • Hidden characters: Copy-paste may include invisible
                                            characters
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  • Single quotes: JSON requires double quotes for strings
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  • Trailing commas: Not allowed in JSON (unlike JavaScript)
                                        
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  • Comments: JSON doesn't support comments
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Our tool highlights the exact location of errors and suggests fixes.

                                

                            

                        

                        

                            

                                
                            

                            

                                

                                    
Yes, all processing happens in your browser - your JSON data
                                        never leaves your computer.

                                    
Key security features:

                                    
    
                                        
  • No server-side processing
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  • No network requests with your data
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  • No storage of your JSON content
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  • You can even use the tool offline
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While they look similar, key differences include:

                                    

                                        
                                            

                                                Feature
                                                JSON
                                                JavaScript
                                            

                                        
                                        
                                            

                                                Quotes
                                                Double quotes only
                                                Single or double quotes
                                            

                                            

                                                Trailing commas
                                                Not allowed
                                                Allowed
                                            

                                            

                                                Comments
                                                Not allowed
                                                Allowed
                                            

                                            

                                                Functions/Dates
                                                Not supported
                                                Supported
                                            

                                        
                                    

                                    
Our tool helps convert between them by enforcing JSON standards.

                                

                            

                        

                        

                            

                                
                            

                            

                                

                                    
For extremely large JSON files (several MB):

                                    
    
                                        
  • Split the file into smaller chunks
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  • Use a desktop application for better performance
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  • Consider streaming parsers for processing
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  • Validate sections separately if possible
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Our web tool works best with JSON documents under 1MB for optimal performance.
                                    

                                

                            

                        

                    

                

            


            

                
Pro Tips

                
    
                    
  • Use Ctrl+Z to undo changes in the input field
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  • The error indicator shows exact character position of problems
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  • Bookmark formatted JSON with # in URL to share examples
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  • For API development, validate responses before parsing
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  • When debugging:
                        
      
                            
    • Copy error messages to search for solutions
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    • Validate JSON at each step of generation
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    • Compare with known-good examples
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    •