Toolwise

JSON Formatter

Paste any JSON and instantly get a clean, indented, syntax-highlighted version — with clear error messages if it's invalid.

How to use JSON Formatter

  1. 1Paste or type your JSON into the editor.
  2. 2Click Format to beautify it, or Minify to compress it to a single line.
  3. 3If the JSON is invalid, the error message shows the line and reason.
  4. 4Copy the result or download it as a .json file.

About JSON Formatter

Minified or poorly-indented JSON is hard to read and debug. This formatter parses your JSON, checks it's valid, and re-prints it with consistent indentation and syntax highlighting so you can quickly scan the structure.

Benefits

  • Instantly spot syntax errors with precise line numbers instead of guessing.
  • Turn minified API responses into a readable structure for debugging.
  • Works entirely in your browser — nothing you paste is sent to a server.

Common mistakes

  • Using trailing commas or single quotes, which are valid in JavaScript objects but not in strict JSON.
  • Forgetting that JSON keys must always be double-quoted strings.

Frequently Asked Questions

No. Formatting and validation happen entirely in your browser using JavaScript — your data never leaves your device.

Formatting adds indentation and line breaks for readability. Minifying strips all unnecessary whitespace to produce the smallest possible file size.

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