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JSON Formatter & Validator

Instantly format messy JSON into readable, properly indented code. Validate JSON syntax and get clear error messages pinpointing exactly where issues are. Minify JSON to a single compact line for APIs and production use. All processing runs entirely in your browser — no data transmitted.

How to use the JSON Formatter

  1. Paste your JSON into the input box on the left.
  2. Click Format to pretty-print with indentation.
  3. Click Minify to compress to a single line.
  4. Copy the result with the copy button.

Frequently Asked Questions

Can the JSON validator detect syntax errors?▼
Yes. It shows the exact error message with line and column number when your JSON contains invalid syntax, such as missing commas, unclosed brackets, or invalid values.
What is JSON minification?▼
JSON minification removes all whitespace, newlines, and indentation to produce the most compact valid JSON possible. This reduces file size and is standard practice for API responses and production configs.
Is my JSON data sent to a server?▼
No. All formatting, validation, and minification is done locally in your browser using JavaScript. Your data never leaves your device.
What JSON specification does the validator follow?▼
It follows the ECMA-404 JSON standard, which is the same spec used by JSON.parse() in all modern browsers and Node.js.