Utilities Web
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JSON Formatter & Validator

Format, minify, and validate JSON

How to Use

  1. Paste JSON data in the input field on the left
  2. Click the "Format" button to convert to a readable format with indentation
  3. Click the "Compress" button to convert to a minimal format without whitespace
  4. You can choose indent width from 2 spaces, 4 spaces, or tabs
  5. If there is a syntax error, the error position is displayed

Use Cases

  • When formatting API response JSON data for easy reading and verification
  • When formatting configuration files (such as package.json)
  • When compressing JSON data to reduce data size
  • When quickly identifying and fixing JSON syntax errors

Frequently Asked Questions

How large can JSON be processed? ▼

As long as it is within the browser's memory limit, JSON of several MB can be processed without any problem. However, if the file is very large, the browser may become slow.

Can I validate (check syntax) JSON? ▼

Yes, it automatically checks the syntax of the input JSON. If there is an error, it displays the error position with line and column numbers, making it easy to fix.

Is the input data sent to a server? ▼

No, all processing is completed on the browser. Input data is never sent to the outside. You can safely format confidential data.

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