JSON Formatter

Format, validate, and explore JSON in a tree view

Format, validate, and pretty-print JSON with syntax highlighting. Paste raw JSON to beautify it with a custom indent or minify it to a single line; invalid input shows a clear parse error. Everything runs locally in your browser.

Input JSON

Output JSON

Minify output

{
  "name": "Alice",
  "age": 30,
  "active": true,
  "items": [
    "x",
    "y"
  ]
}

How to use

Paste or type your JSON into the input.
The tool validates it instantly and reports the first syntax error if any.
Choose an indent width to pretty-print, or minify to a single line.
Expand and collapse nodes in the tree view to explore nested objects and arrays.

Examples

Pasting {"a":1,"b":[2,3]} and formatting produces an indented, colour-highlighted tree.
If a comma or brace is missing, the validator points to the line and character where parsing failed.

Verify outputs before using in production. No warranty — see Terms.