JSON Formatter & Beautifier

A JSON formatter (also called a JSON beautifier or JSON pretty printer) takes raw or minified JSON text and reformats it with consistent indentation and line breaks, making it easy to read and understand. Developers use JSON formatters daily when working with API responses, configuration files, database exports, and log data.

This free online JSON formatter runs entirely in your browser — no data is ever sent to a server. Paste your JSON, click Format, and get clean, indented output instantly. It also works as a JSON validator, highlighting syntax errors with the exact line and character position so you can fix them immediately.

These terms are often used interchangeably, but they refer to slightly different operations:

• ▸JSON Formatter / Beautifier / Pretty Print — adds indentation and newlines to make JSON human-readable. Useful when reading API responses or debugging data structures.
• ▸JSON Minifier — removes all whitespace to produce compact JSON. Reduces payload size for production APIs and config files.
• ▸JSON Validator — checks whether JSON is syntactically correct. Reports errors with line and character numbers. This tool validates automatically as you type.

This tool does all three. You can prettify, minify, and validate JSON in one place — with an interactive tree viewer to explore nested structures.

The JSON validator highlights errors instantly. Here are the most common JSON mistakes:

• ▸Trailing comma — {"key": "value",} — JSON does not allow a comma after the last item. Remove the trailing comma.
• ▸Unquoted keys — {key: "value"} — all JSON keys must be double-quoted strings.
• ▸Single quotes — {'key': 'value'} — JSON requires double quotes, not single quotes.
• ▸Comments — JSON does not support // comments or /* block comments */. Remove all comments before parsing.
• ▸Undefined or NaN values — undefined and NaN are JavaScript values, not valid JSON. Use null instead.

1. 1.Paste your JSON into the input panel on the left, or type directly.
2. 2.Click Format to prettify, or Minify to compress.
3. 3.If there are errors, they appear below the input with the exact line and column.
4. 4.Use the tree viewer on the right to explore nested objects and arrays. Click any node to collapse or expand it.
5. 5.Copy the output to clipboard or download it as a .json file.