DevToolKit

Free JSON Formatter & Validator Online

Format, minify, and validate JSON data instantly in your browser. Syntax highlighting, error detection with line numbers, and one-click copy.

How to Use

  1. Paste your JSON data into the input textarea
  2. Click Format to pretty-print with indentation and syntax highlighting
  3. Click Minify to compress JSON by removing whitespace
  4. Click Validate to check if your JSON is valid (errors show line numbers)
  5. Use Copy Output to copy the result to your clipboard
  6. Change indent size (2 spaces, 4 spaces, or tab) using the dropdown