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JSON Formatter

Paste, format, validate, and minify JSON — all client-side.

Input
Output 

            

        

    







JSON (JavaScript Object Notation) is the most widely used data format for APIs and configuration files. When JSON is minified — stripped of whitespace and line breaks — it becomes nearly impossible to read. A JSON formatter parses the raw string, validates its syntax, and re-outputs it with consistent indentation.
This tool uses your browser's built-in JSON.parse() and JSON.stringify() methods with a 2-space indent. If the JSON is invalid, you'll see the exact syntax error and its position, making it easy to debug malformed API responses or config files. Common errors include trailing commas, single quotes instead of double quotes, and unescaped special characters.
Minification does the reverse — it strips all unnecessary whitespace to reduce payload size. This is useful when embedding JSON in URLs, localStorage, or HTTP headers where every byte counts. All processing happens entirely in your browser — no data is sent to any server.




This tool in other languages:


Français:
Formateur et validateur JSON


Español:
Formateador y validador JSON


Deutsch:
JSON-Formatierer und Validator


Português:
Formatador e validador JSON


日本語:
JSONフォーマッター＆バリデーター


中文:
JSON 格式化和验证工具


한국어:
JSON 포맷터 및 검증기


العربية:
منسق ومدقق JSON








  
Frequently asked questions


  

    How do I format messy JSON online for free?
    

      
Paste your JSON into the input area and click Format. The tool will indent, align, and color-code the JSON instantly. Click Copy to grab the result. Everything runs in your browser — no signup, no upload, no tracking.

    

  


  

    What is the difference between JSON format and JSON minify?
    

      
Format (or prettify) adds indentation and line breaks so JSON is human-readable. Minify removes all whitespace to shrink the file for production use or API payloads. Both modes validate your JSON first — if it's malformed, you'll see an error with the exact position.

    

  


  

    How do I fix invalid JSON errors?
    

      
Common causes are trailing commas, unquoted keys, single quotes instead of double quotes, and missing brackets. Paste your JSON and click Format — the validator will point to the exact line and character where the error occurs so you can fix it.

    

  


  

    Is it safe to paste sensitive JSON data into an online formatter?
    

      
With DeskTools, yes. All processing happens inside your browser using JavaScript — nothing is uploaded to a server, logged, or stored. You can safely format JSON containing API keys, tokens, or personal data. For extra peace of mind, load the page once and work offline.

    

  


  

    Can this JSON formatter handle large files?
    

      
Yes. Because everything runs locally, there's no upload limit. Performance depends on your device's memory, but most modern browsers handle JSON files of several megabytes without issues. For very large files (100MB+), a native desktop tool may be faster.