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Free Online JavaScript Formatter & Beautifier

Format and beautify your JavaScript, TypeScript, and JSX code in real-time. Paste any raw, minified, or messy JS code and get clean, properly indented output with syntax highlighting. No uploads, no servers, 100% private.

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JavaScript FormatterFormatted

Indent:

Code Input

import React, { useState, useEffect } from 'react';
import { BrowserRouter, Routes, Route } from 'react-router-dom';

const API_BASE_URL = 'https://api.example.com/v1';

/**
 * Fetches user data from the API.
 * @param {string} userId - The user's unique identifier
 * @returns {Promise<Object>} The user data object
 */
async function fetchUserData(userId) {
  try {
    const response = await fetch(`${API_BASE_URL}/users/${userId}`);
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    const data = await response.json();
    return data;
  } catch (error) {
    console.error('Failed to fetch user:', error);
    throw error;
  }
}

class UserProfile {
  #privateToken = null;

constructor({ id, name, email, role = 'user' }) {
    this.id = id;
    this.name = name;
    this.email = email;
    this.role = role;
  }

get displayName() {
    return this.name || this.email.split('@')[0];
  }

set accessToken(token) {
    if (!token || typeof token !== 'string') {
      throw new Error('Invalid token');
    }
    this.#privateToken = token;
  }

toJSON() {
    const { id, name, email, role } = this;
    return { id, name, email, role };
  }
}

const App = () => {
  const [users, setUsers] = useState([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState(null);

useEffect(() => {
    const loadUsers = async () => {
      try {
        setLoading(true);
        const data = await fetchUserData('all');
        setUsers(data.map(u => new UserProfile(u)));
      } catch (err) {
        setError(err.message);
      } finally {
        setLoading(false);
      }
    };
    loadUsers();
  }, []);

if (loading) return <div className="loader">Loading...</div>;
  if (error) return <div className="error">Error: {error}</div>;

return (
    <div className="container">
      <h1>User Directory</h1>
      <div className="grid">
        {users.map((user) => (
          <div key={user.id} className="card">
            <h2>{user.displayName}</h2>
            <p>{user.email}</p>
            <span className={`badge badge-${user.role}`}>
              {user.role}
            </span>
          </div>
        ))}
      </div>
    </div>
  );
};

export default App;

Formatted Output

1import React, {

2 useState, useEffect

4from 'react';

5import {

6 BrowserRouter, Routes, Route

8from 'react-router-dom';

9const API_BASE_URL = 'https://api.example.com/v1';

10/**

11 * Fetches user data from the API.

12 * @param {string} userId - The user's unique identifier'

13 * @returns {Promise<Object>} The user data object

14 */

15async function fetchUserData(userId) {

16 try {

17 const response = await fetch(`${API_BASE_URL}/users/${userId}`);

18 if(!response.ok) {

19 throw new Error(`HTTP error! status: ${response.status}`);

20 }

21 const data = await response.json();

22 return data;

23 }

24 catch(error) {

25 console.error('Failed to fetch user:', error);

26 throw error;

27 }

28}

29class UserProfile {

30 #privateToken = null;

31 constructor( {

32 id, name, email, role = 'user'

33 })

34 {

35 this.id = id;

36 this.name = name;

37 this.email = email;

38 this.role = role;

39 }

40 get displayName() {

41 return this.name || this.email.split('@')[0];

42 }

43 set accessToken(token) {

44 if(!token || typeof token !== 'string') {

45 throw new Error('Invalid token');

46 }

47 this.#privateToken = token;

48 }

49 toJSON() {

50 const {

51 id, name, email, role

52 }

53 = this;

54 return {

55 id, name, email, role

56 };

57 }

58}

59const App =() => {

60 const[users, setUsers] = useState([]);

61 const[loading, setLoading] = useState(true);

62 const[error, setError] = useState(null);

63 useEffect(() => {

64 const loadUsers = async() => {

65 try {

66 setLoading(true);

67 const data = await fetchUserData('all');

68 setUsers(data.map(u => new UserProfile(u)));

69 }

70 catch(err) {

71 setError(err.message);

72 }

73 finally {

74 setLoading(false);

75 }

76 };

77 loadUsers();

78 },

79 []);

80 if(loading) return <div className="loader">Loading...</div>;

81 if(error) return <div className="error">Error: {

82 error

83 }

84 </div>;

85 return(

86 <div className="container">

87 <h1>User Directory</h1>

88 <div className="grid">

89 {

90 users.map((user) =>(

91 <div key= {

92 user.id

93 }

94 className="card">

95 <h2> {

96 user.displayName

97 }

98 </h2>

99 <p> {

100 user.email

101 }

102 </p>

103 <span className= {

104 `badge badge-${user.role}`

105 }

106 >

107 {

108 user.role

109 }

110 </span>

111 </div>

112 ))

113 }

114 </div>

115 </div>

116 );

117};

118export default App;

119

Chars: 2267Lines: 119Indent: 2 spaces

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How to Use

How to Use the JavaScript Formatter

Paste Your Code

Copy your JavaScript, TypeScript, or JSX code from any source — your code editor, a web page, or a file. Paste it into the input editor.

Auto-Format Instantly

The tool automatically formats your code with proper indentation, line breaks, and color syntax highlighting. Strings, keywords, functions, and comments are clearly distinguished.

Copy or Download

Click the copy button to copy the formatted code to your clipboard, or download it as a .js file. Ready to use in your project.

Features

Powerful JavaScript Formatting Features

Everything you need to format and beautify JavaScript code — all in one free tool.

⚡

Real-Time Formatting

See your code formatted instantly as you type or paste. No buttons to click — just paste and go.

🎨

Syntax Highlighting

Color-coded keywords, strings, numbers, functions, classes, and comments make your code easy to read and debug.

🎯

Customizable Indentation

Choose from 2 or 4 space indentation to match your project's coding conventions.

⚛️

JSX Support

Properly formats React JSX syntax including self-closing tags, nested elements, and expressions.

📋

Copy to Clipboard

Copy formatted code to your clipboard with a single click. Ready to paste into your code editor.

💾

Download as File

Download your formatted code as a .js file. Perfect for saving updated files.

🔢

Line Numbers

Every line is numbered for easy reference. Debug faster by sharing exact line numbers.

🔒

100% Client-Side

All processing happens in your browser. Your code never leaves your device — no uploads, no servers, no privacy concerns.

Why This Tool

Why Use Our JavaScript Formatter

The simplest, fastest way to format JavaScript online. No sign-up, no limits, no data leaving your browser.

100% Free

No hidden fees, no premium plans, no usage limits. Format as much code as you need, as often as you want.

Privacy First

Your code never leaves your browser. Everything is processed locally — no server uploads, no data logging.

Modern JS Support

Handles ES6+, arrow functions, async/await, destructuring, spread operator, template literals, classes, modules, and JSX.

Developer-Friendly

Built by developers for developers. Clean, consistent output that matches modern coding standards.

Key Highlights

No sign-up or registration required
Processes everything in your browser — zero server uploads
Supports ES6+, TypeScript, and JSX/TSX syntax
Handles arrow functions, async/await, classes, and modules
Works on any device — desktop, tablet, or mobile
Regularly updated with new features and improvements

FAQ

Frequently asked questions

What is a JavaScript formatter?

A JavaScript formatter (also called a JS beautifier) takes raw, minified, or messy JavaScript code and reformats it with proper indentation, line breaks, and consistent spacing. This makes code much easier to read, debug, and maintain.

Is this JavaScript formatter really free?

Yes, completely free. There are no hidden charges, no usage limits, and no premium features locked behind a paywall. Use it as much as you need, whenever you need it.

Is my code data secure?

Absolutely. All processing happens entirely in your browser using JavaScript. Your code is never sent to any server, stored, or logged.

Does it support TypeScript?

Yes! The formatter supports TypeScript syntax including type annotations, interfaces, enums, generics, and type aliases.

Does it support JSX/React?

Yes. The formatter properly handles JSX syntax including self-closing tags, nested elements, expressions in curly braces, and React component patterns.

What JavaScript features are supported?

The formatter supports all modern JavaScript including: arrow functions, async/await, classes, template literals, destructuring, spread/rest operators, modules (import/export), optional chaining, nullish coalescing, and more.

Can I customize the indentation?

Yes! You can choose between 2-space or 4-space indentation using the dropdown in the toolbar.

Do I need to install anything?

No installation required. The JavaScript formatter works entirely in your web browser. Just open the page and start formatting. No downloads, no plugins, no setup.

Can I use this on my phone?

Yes, the tool is fully responsive and works on all devices — desktops, tablets, and smartphones.