How to Use the JSON Formatter

1. Paste your JSON — Copy any raw, minified, or malformed JSON from an API response, config file, or database and paste it into the input area.

2. Choose indentation — Select 2 spaces, 4 spaces, or tab indentation to match your project's coding conventions.

3. Optionally sort keys — Enable alphabetical key sorting to make large objects easier to navigate and compare.

4. Click Format JSON — The tool parses your input, validates it, and displays a syntax-highlighted, beautifully indented result.

5. Copy or download — Use the Copy button to grab the output or click Download to save it as a file for later use.

Key Features

How It Works

The JSON Formatter uses the browser's native JSON.parse() method to validate and parse your input. This is the same JSON engine used by JavaScript itself — strict, fast, and specification-compliant.

Once parsed, JSON.stringify() is called with your chosen indentation setting to re-serialize the JavaScript object back into a formatted JSON string. If you select key sorting, the object is recursively sorted before serialization.

Syntax highlighting is applied by walking through the formatted string with a regular expression that identifies and wraps JSON tokens — keys, string values, numbers, booleans, and nulls — in colored <span> elements before rendering into the output panel.

If JSON.parse() throws an error, the error message is captured and displayed directly to help you locate and fix the syntax problem. For minification, the same parse step runs, then JSON.stringify() is called without any indentation argument, producing the most compact valid JSON possible.

Practical Examples

{"product_id":4821,"name":"Banarasi Silk Saree","price_inr":4599,"in_stock":true,"seller":"Mumbai Textiles","tags":["saree","silk","wedding"]}

{"apiKey":"AIzaSy...","authDomain":"myapp.firebaseapp.com","projectId":"myapp-india","storageBucket":"myapp.appspot.com","messagingSenderId":"123456789","appId":"1:123:web:abc"}

{"status":"error","code":422,"message":"Validation failed","errors":{"email":["Email is required"],"phone":["Invalid format"]}}

{"name":"storedropship-api","version":"2.1.0","scripts":{"start":"node server.js","dev":"nodemon server.js"},"dependencies":{"express":"^4.18.2","mongoose":"^7.4.0"}}

What Is JSON Formatter?

A JSON Formatter is a developer tool that takes JavaScript Object Notation (JSON) data — which is often compressed into a single unreadable line — and restructures it with proper indentation, line breaks, and spacing to make it easy for humans to read and understand. JSON is the most widely used data format for APIs, configuration files, NoSQL databases, and web application data exchange. Raw JSON from APIs is almost always minified (no spaces) to reduce payload size, which makes it extremely difficult to read or debug manually. A JSON formatter solves this instantly.

Beyond formatting, a good JSON tool also validates the JSON against the official specification (RFC 8259), catching common mistakes like trailing commas, single-quoted strings, unquoted keys, and mismatched brackets — errors that cause silent failures in many programming environments.

JSON Formatter in Multiple Languages

Frequently Asked Questions