JSON Formatter
Format, beautify, validate, and minify your JSON data instantly.
JSON formatter and validator online
This JSON formatter beautifies (indents) and validates your JSON, and can also minify it. If there’s a syntax error, it points it out. Great for reading API responses, debugging and tidying config. Everything runs in your browser, with nothing uploaded.
What JSON is
JSON (JavaScript Object Notation) is a text format for exchanging data: objects in braces {}, lists in brackets [], and key: value pairs. It’s readable, lightweight and the de facto standard for web APIs.
Rules that commonly break JSON
- Keys and strings use double quotes, not single.
- A trailing comma after the last item is not allowed.
- Valid values are string, number,
true,false,null, object or array. - Comments are not allowed.
Format vs minify
Formatting adds line breaks and indentation so JSON is readable. Minifying strips whitespace to shrink the size, ideal before sending over the network. Both represent exactly the same data.
Frequently asked questions
Why does my JSON error? Most often: single quotes, an extra comma at the end, or an unclosed brace/bracket.
Is my data sent to a server? No; it’s processed in your browser.
Difference between JSON and a JavaScript object? JSON is just text with strict rules; a JS object is an in-memory structure and more permissive.