JSON Formatter: Pretty Print & Minify JSON

Format JSON with pretty print, minify, and custom indentation. Transform JSON between readable and compact formats. Free, no registration required.

Last updated: March 2026 • Formats: Pretty-print, Minify, Sort Keys

What is JSON Formatting?

JSON formatting transforms JSON between two main states:

Pretty-Printed JSON: Readable, indented, with line breaks. Easy for humans to read and edit.

Minified JSON: Compact, no whitespace, single line. Ideal for APIs, file storage, and transmission.

JSON Visualiser lets you switch between formats instantly, with options for indentation size, key sorting, and more.

Formatting Options

Pretty Print (Beautify)

Transform compact JSON into readable, indented format:

// Minified{"name":"John","age":30,"active":true}// Pretty-Printed (2 spaces){  "name": "John",  "age": 30,  "active": true}

Options:

• Indentation: 2, 4, or custom number of spaces
• Sort keys: Alphabetical or preserve order
• Add trailing newlines: Yes or no
• Space after colons: Yes or no

Minify (Compress)

Transform readable JSON into compact format:

// Pretty-Printed{  "name": "John",  "age": 30,  "active": true}// Minified{"name":"John","age":30,"active":true}

Benefits:

• Smaller file size (up to 40% reduction)
• Faster transmission over network
• Ideal for API responses
• Reduces storage requirements

Sort Keys Alphabetically

Reorder object keys alphabetically for consistency:

// Original order{  "name": "John",  "age": 30,  "city": "NYC"}// Sorted keys{  "age": 30,  "city": "NYC",  "name": "John"}

Benefits:

• Easier to find keys visually
• Consistent order across files
• Better for diff comparisons
• Git-friendly

How to Format JSON

Step 1: Open JSON Visualiser

Navigate to the JSON Visualiser homepage. No sign-up required.

Step 2: Paste or Type JSON

Paste your JSON into the editor, or type directly. Monaco editor provides syntax highlighting.

Step 3: Choose Format Option

Use the formatting toolbar:

• Pretty Print: Add indentation and line breaks
• Minify: Remove all whitespace
• Sort Keys: Alphabetically reorder object keys
• Custom Indent: Choose 2, 4, or custom spaces

Step 4: Copy or Export

Copy the formatted JSON to your clipboard, or use the tree view to explore the structure.

Format Examples

Configuration Files

Pretty-print configuration files for readability:

{  "database": {    "host": "localhost",    "port": 5432,    "name": "myapp",    "credentials": {      "username": "admin",      "password": "secret"    }  },  "api": {    "timeout": 30000,    "retries": 3  }}

API Responses

Minify API responses for faster transmission:

{  "status": "success",  "data": { "id": 123, "name": "Product", "price": 99.99 },  "timestamp": 1640995200}

Data Export

Sort keys for consistent data exports:

{  "email": "user@example.com",  "id": "abc-123",  "name": "John Doe",  "role": "admin"}

Indentation Options

2 Spaces (Default)

Compact but readable:

{  "key": "value",  "nested": {    "item": "data"  }}

Best for: Most use cases, modern coding standards

4 Spaces

More indentation, clearer nesting:

{  "key": "value",  "nested": {    "item": "data"  }}

Best for: Very nested JSON, learning purposes

Tabs (Tab Character)

Uses actual tab characters:

{  "key": "value",  "nested": {    "item": "data"  }}

Best for: Editor-specific preferences, legacy systems

Pretty Print vs. Minify

Formatting Best Practices

For Human Readers

Use pretty-print formatting:

• Indentation: 2 or 4 spaces
• Sort keys alphabetically
• Add trailing newlines
• Space after colons for readability

For APIs & Storage

Use minified formatting:

• Remove all whitespace
• Skip key sorting (preserve order)
• No trailing newlines
• Minify before network transmission

For Version Control

Use consistent formatting:

• Same indentation across files
• Sort keys alphabetically
• Use pretty-print for diffs
• Run linters to enforce format

For JSON Patches & Diffs

Use pretty-print with consistent order:

• Easier to see what changed
• Smaller diffs when consistent
• Better for code reviews

Bulk Formatting

Format multiple JSON files:

# Format all .json files with jqfind . -name "*.json" -exec jq '.' {} > {}.formatted && mv {}.formatted {} \;# Minify all .json filesfind . -name "*.json" -exec jq -c '.' {} > {}.minified && mv {}.minified {} \;

Or paste multiple JSON objects into JSON Visualiser and format them one by one.

Advanced Formatting

Preserve Order

JavaScript objects maintain key insertion order (ES2015+). By default, JSON Visualiser preserves this order unless you choose to sort keys.

Unicode Characters

JSON supports Unicode characters in strings. Pretty-printing doesn't escape Unicode by default, but you can choose to escape for specific use cases.

Special Characters

Pretty-printing handles special characters correctly:

• Newlines in strings: \n
• Tabs in strings: \t
• Quotes: \" or \'
• Backslashes: \\

Date Formatting

JSON has no native date type. Dates are typically strings in ISO 8601 format:

{  "createdAt": "2026-03-04T12:00:00Z",  "updatedAt": "2026-03-04T14:30:00Z"}

Formatting in Different Languages

JavaScript

const data = { name: "John", age: 30 };const pretty = JSON.stringify(data, null, 2); // 2-space indentconst minified = JSON.stringify(data);

Python

import jsondata = {"name": "John", "age": 30}pretty = json.dumps(data, indent=2)minified = json.dumps(data, separators=(',', ':'))

PHP

$data = ["name" => "John", "age" => 30];$pretty = json_encode($data, JSON_PRETTY_PRINT);$minified = json_encode($data);

Format, pretty-print, and minify JSON instantly. No registration, instant load, and multiple formatting options for every use case.

References: JSON.stringify() documentation, Python json module, PHP json_encode().