JSON Formatter
Format, validate, and minify JSON with syntax highlighting and error detection.
Input
Output
Output will appear here after formatting…
How the JSON Formatter Works
Paste raw or minified JSON into the input box, then click Format to pretty-print it with your chosen indentation, Minify to strip whitespace, or Validate to check for syntax errors without changing the output. The Tree view lets you expand and collapse nested objects and arrays interactively. Syntax highlighting uses colour to distinguish keys, strings, numbers, booleans, and null values.
Frequently Asked Questions
+What is a JSON formatter?
A JSON formatter (also called a JSON beautifier or pretty-printer) takes minified or poorly indented JSON and reformats it with consistent indentation so it is easy to read and understand. This tool lets you choose 2-space, 4-space, or tab indentation.
+How do I validate JSON online?
Paste your JSON into the input box and click Validate. The tool uses the browser's native JSON.parse() to check your JSON. If there's a problem, it reports the exact line and column where the error occurs and describes what went wrong.
+What is the difference between Format and Minify?
Format (beautify) adds indentation and line breaks to make JSON human-readable. Minify does the opposite — it removes all unnecessary whitespace to produce the smallest possible JSON string, ideal for sending over a network or storing in a file where size matters.
+What does a JSON beautifier do?
JSON beautifier is another name for a JSON formatter. It reformats compact JSON into a structured, indented layout with syntax highlighting for keys, strings, numbers, booleans, and null values — making it far easier to read and debug.
+Why is my JSON invalid?
Common causes: trailing commas after the last item in an object or array (not allowed in JSON, unlike JavaScript), single quotes instead of double quotes, unquoted keys, comments (JSON has no comment syntax), or a missing closing bracket/brace. The validator will tell you the exact line and column of the first error.
+What is the difference between JSON and JavaScript objects?
JSON is a text format and a strict subset of JavaScript object notation. Unlike JS objects, JSON requires double-quoted keys and string values, does not allow trailing commas, does not support undefined or functions as values, and has no comment syntax. A valid JSON file is also valid JavaScript, but not vice versa.