JSON Formatter

Format and validate JSON for readability

Features

Switch between 4 indents

Choose from 2 or 4 spaces, tabs, and minify

Pinpoint syntax errors

Instantly point out the line and column of invalid JSON

Supports copy and download

Get and save the formatted result with one click

Instant check with samples

Quickly check behavior with valid and invalid examples

How to Use

Enter the JSON data

Paste a JSON string in the input field, or load it from a sample

Select the indent format

Choose one of 2 spaces, 4 spaces, tabs, or minify via radio buttons

Press the format button to run

Press the format button to parse and validate, with the result shown on the right

Copy and save the formatted result

Save the formatted JSON with the copy button or download button

Use Cases

Check API responses

Format API output returned on a single line to visually grasp the structure

Tidy up configuration files

Tidy package.json, tsconfig, and the like with uniform indentation

Debug JSON syntax

Quickly identify the cause of broken JSON with line and column error indications

Minify JSON to reduce size

Save data traffic and storage with the minimal size, free of extra whitespace

Read data for learning

Expand nested structures for readability to understand the data hierarchy

Basic Knowledge

What is JSON?

JSON is a lightweight data format that represents data as a combination of "name-value pairs" and arrays. It is used as the de facto standard for data exchange between systems, such as in API responses and configuration files.

Common Syntax Errors

Trailing Comma：A trailing comma is an extra comma after the last element. While permitted in JavaScript, it causes a syntax error in JSON.
Single Quotes：JSON strings and key names must be enclosed in double quotes ("). Using single quotes (') will result in an error.
Comments：JSON does not have a comment syntax, so writing // or /* */ will make the JSON invalid.