JavaScript Beautifier Free Online Tool 2026

Last updated March 22, 2026

Example: Minified Code → Beautified

// Before (minified):
function calculateTotal(items){return items.reduce((sum,item)=>sum+item.price*item.quantity,0);}const cart=[{price:10,quantity:2},{price:25,quantity:1}];console.log(calculateTotal(cart));

// After (beautified, 2-space indent):
function calculateTotal(items) {
  return items.reduce((sum, item) => sum + item.price * item.quantity, 0);
}

const cart = [
  { price: 10, quantity: 2 },
  { price: 25, quantity: 1 }
];

console.log(calculateTotal(cart));

Example: Inconsistently Formatted Code

// Before:
const user={name:'Alice',age:30,address:{city:'New York',zip:'10001'}}
function greet(user){
if(user.name){
console.log('Hello '+user.name)
}else{
console.log('Hello stranger')
}}

// After (beautified):
const user = {
  name: 'Alice',
  age: 30,
  address: {
    city: 'New York',
    zip: '10001'
  }
};

function greet(user) {
  if (user.name) {
    console.log('Hello ' + user.name);
  } else {
    console.log('Hello stranger');
  }
}

Example: React JSX Component

// Before (minified JSX):
const Button=({label,onClick,disabled=false})=><button className={`btn ${disabled?'btn-disabled':'btn-primary'}`} onClick={onClick} disabled={disabled}>{label}</button>;

// After (beautified JSX):
const Button = ({ label, onClick, disabled = false }) => (
  <button
    className={`btn ${disabled ? 'btn-disabled' : 'btn-primary'}`}
    onClick={onClick}
    disabled={disabled}
  >
    {label}
  </button>
);

Example: Class Syntax

// Before:
class EventEmitter{constructor(){this.events={}}on(event,listener){if(!this.events[event])this.events[event]=[];this.events[event].push(listener)}emit(event,...args){if(this.events[event])this.events[event].forEach(l=>l(...args))}}

// After:
class EventEmitter {
  constructor() {
    this.events = {};
  }

  on(event, listener) {
    if (!this.events[event]) this.events[event] = [];
    this.events[event].push(listener);
  }

  emit(event, ...args) {
    if (this.events[event]) {
      this.events[event].forEach(l => l(...args));
    }
  }
}

Example: Async/Await with Error Handling

// Before:
async function loadDashboard(){try{const[users,orders,stats]=await Promise.all([fetchUsers(),fetchOrders(),fetchStats()]);return{users,orders,stats}}catch(err){console.error('Dashboard load failed:',err);throw err}}

// After:
async function loadDashboard() {
  try {
    const [users, orders, stats] = await Promise.all([
      fetchUsers(),
      fetchOrders(),
      fetchStats()
    ]);
    return { users, orders, stats };
  } catch (err) {
    console.error('Dashboard load failed:', err);
    throw err;
  }
}

Formatting Options

• Indent style: 2 spaces (default), 4 spaces, or tabs
• Quote style: single quotes, double quotes, or preserve original
• Semicolons: always add, never add, or preserve original
• Trailing commas: none, ES5 (objects/arrays), or all (including function params)
• Print width: max line length before wrapping (default: 80)
• Bracket spacing: spaces inside object braces { key: value } vs {key: value}

Example: Quote Style Normalization

// Before (mixed quotes):
const config = {
  host: "localhost",
  port: '3000',
  name: "my-app",
  debug: 'true'
};

// After (normalized to single quotes):
const config = {
  host: 'localhost',
  port: '3000',
  name: 'my-app',
  debug: 'true'
};

Example: TypeScript Code

// Before:
interface User{id:number;name:string;email:string;role:'admin'|'user'}function getUserById(id:number):Promise<User|null>{return db.query<User>('SELECT * FROM users WHERE id = ?',[id]).then(rows=>rows[0]??null)}

// After:
interface User {
  id: number;
  name: string;
  email: string;
  role: 'admin' | 'user';
}

function getUserById(id: number): Promise<User | null> {
  return db
    .query<User>('SELECT * FROM users WHERE id = ?', [id])
    .then(rows => rows[0] ?? null);
}

Paste any JavaScript, TypeScript, or JSX code into the beautifier, choose your formatting preferences, and get clean, consistently formatted output instantly.

// Before:
const fetchUser=async(id)=>{const{data,error}=await api.get(`/users/${id}`);if(error)throw new Error(error.message);return data;};

// After:
const fetchUser = async (id) => {
  const { data, error } = await api.get(`/users/${id}`);
  if (error) throw new Error(error.message);
  return data;
};