Format, validate, beautify and minify JSON data instantly in your browser — with syntax highlighting and
error detection.
Indent:
Input JSON
Ready — paste JSON to begin
Formatted Output
Formatted JSON will appear here…
—
🧩 What Is JSON?
JSON (JavaScript Object Notation) is a lightweight, human-readable data interchange
format. It's the most widely used format for APIs, configuration files, and data storage in modern
web applications.
How to Use This Tool
Format / Beautify — Converts compact or messy JSON into a readable, indented
format.
Minify — Removes all whitespace to produce the smallest possible JSON string.
Useful for reducing data transfer sizes.
Validate — Checks if your JSON is syntactically valid without reformatting it.
Color Syntax — Output is highlighted: keys in pink, strings in green, numbers
in blue, booleans in amber.
Download — Save the formatted JSON as a .json file.
JSON Syntax Rules
Data is in key/value pairs: {"key": "value"}
Keys must be strings in double quotes — single quotes are invalid.
Values can be: string, number, object, array, boolean, null
Arrays use square brackets: [1, 2, 3]
No trailing commas — {"a": 1,} is invalid.
No comments — JSON does not support // comments
Common JSON Errors
Missing or mismatched braces/brackets ({} or [])
Using single quotes instead of double quotes for strings
Trailing commas after the last item in an object or array
Unescaped special characters in strings (use \", \\, \n)
Using undefined — JSON has no undefined, only null