JSON Formatter
Free Json Formatter for tools. Free online tool with accurate results using verified formulas. Includes worked examples, FAQ, and instant calculations.
Formula
Format: JSON.stringify(JSON.parse(input), null, 2) | Minify: JSON.stringify(JSON.parse(input))
The tool first parses the input to validate JSON syntax, then serializes it either with indentation or as a compact one-line string.
Worked Examples
Example 1: Format an API response
Problem:Make a single-line API response easier to review.
Solution:Input: {"user":{"id":123,"name":"John"},"status":"active"}\n\nFormatted output:\n{\n "user": {\n "id": 123,\n "name": "John"\n },\n "status": "active"\n}
Result:Nested objects become readable and easier to debug.
Example 2: Catch invalid syntax
Problem:Why is this JSON invalid: {name: "John", "age": 30,}?
Solution:Two issues exist: the key name is unquoted and there is a trailing comma after the last property. Valid JSON must use double-quoted keys and cannot end an object or array with an extra comma.
Result:The formatter surfaces the parse error before you ship broken JSON.
Example 3: Minify for production
Problem:Shrink a formatted configuration object before deployment.
Solution:Pretty JSON keeps the structure readable during editing. Minified JSON removes line breaks and spaces so the same data takes fewer bytes over the network.
Result:Same data, smaller payload.
Frequently Asked Questions
Why format JSON?
Formatted JSON adds indentation and line breaks so you can inspect nested objects, arrays, and keys quickly. It is much easier to debug than a single minified line.
Why minify JSON?
Minified JSON removes unnecessary whitespace to reduce payload size. That makes network transfers and storage more efficient, especially in production environments.
What makes JSON invalid?
Common errors include trailing commas, unquoted keys, single quotes instead of double quotes, missing braces or brackets, and unescaped special characters inside strings.
Can JSON include comments?
Standard JSON does not allow comments. If you need comments in configuration data, use a different format such as YAML or a JSON-compatible extension like JSON5.