How to Format JSON in JavaScript

Feb 06, 2026 3 min read

JavaScript has built-in support for JSON because it derives from standard JavaScript object syntax. Using JSON.stringify(), you can parse objects and arrays and instantly generate a beautifully formatted multiline string.

Example Code

JavaScript

const jsonString = '{"name":"John","age":30,"city":"New York"}';

const parsedData = JSON.parse(jsonString);
const formattedJson = JSON.stringify(parsedData, null, 2);

console.log(formattedJson);

Common Use Cases

Formatting responses from HTTP requests in Node.js endpoints
Logging human-readable debug structures
Presenting JSON blocks dynamically inside functional web apps

💡 Pro Tips for JavaScript

The third argument indicates how many spaces to insert for indentation.
The second argument (which is null here) is a Replacer function to selectively filter out keys like user passwords before serialization.

Fastest JS Formatter

Why use <code>console.log</code> when you can see your data in a beautiful, interactive tree? Use our client-side tool for instant results.

Try Formatter JSON Minifier