JavaScript Formatter - Code Beautifier

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Format and beautify JavaScript code with proper indentation and spacing. Essential for code review, debugging minified scripts, and maintaining readable codebases. Supports ES6+ syntax.
Advanced JavaScript Formatter & Code Beautifier

Professional JavaScript code formatting tool for developers, code reviewers, and DevOps teams. Transform minified or poorly formatted code into clean, readable JavaScript with intelligent indentation, proper spacing, and consistent styling.

Intelligent code parsing with AST-based formatting Customizable indentation styles (spaces, tabs, mixed) ES6+/TypeScript syntax support with JSX compatibility Automatic code structure analysis and optimization Configurable formatting rules and coding standards Batch processing for entire codebases and projects
Practical Examples
Minified Library Debugging

Transform minified JavaScript into readable code for debugging

BEFORE (Minified JavaScript) 
function getUserData(e,r){const s=new XMLHttpRequest;s.open("GET","/api/users/"+e,!0),s.onreadystatechange=function(){4===s.readyState&&(200===s.status?r(null,JSON.parse(s.responseText)):r(new Error("Request failed: "+s.status),null))},s.send()}const users=[],cache=new Map;async function loadUserProfiles(e){const r=[];for(const s of e){if(cache.has(s)){r.push(cache.get(s));continue}try{const e=await new Promise(((e,r)=>{getUserData(s,((s,t)=>{s?r(s):e(t)}))}));cache.set(s,e),r.push(e)}catch(e){console.error("Failed to load user:",s,e)}}return r}
AFTER (Beautified JavaScript) 
function getUserData(userId, callback) {
    const xhr = new XMLHttpRequest();
    xhr.open("GET", "/api/users/" + userId, true);
    xhr.onreadystatechange = function() {
        if (xhr.readyState === 4) {
            if (xhr.status === 200) {
                callback(null, JSON.parse(xhr.responseText));
            } else {
                callback(new Error("Request failed: " + xhr.status), null);
            }
        }
    };
    xhr.send();
}

const users = [];
const cache = new Map();

async function loadUserProfiles(userIds) {
    const profiles = [];
    
    for (const userId of userIds) {
        if (cache.has(userId)) {
            profiles.push(cache.get(userId));
            continue;
        }
        
        try {
            const profile = await new Promise((resolve, reject) => {
                getUserData(userId, (error, data) => {
                    if (error) {
                        reject(error);
                    } else {
                        resolve(data);
                    }
                });
            });
            
            cache.set(userId, profile);
            profiles.push(profile);
        } catch (error) {
            console.error("Failed to load user:", userId, error);
        }
    }
    
    return profiles;
}
React Component Formatting

Format React components with proper JSX indentation and structure

BEFORE (Minified JavaScript) 
const TodoApp=()=>{const[todos,setTodos]=useState([]);const[inputValue,setInputValue]=useState("");const addTodo=()=>{if(inputValue.trim()){setTodos([...todos,{id:Date.now(),text:inputValue,completed:false}]);setInputValue("");}};const toggleTodo=(id)=>{setTodos(todos.map(todo=>todo.id===id?{...todo,completed:!todo.completed}:todo));};const deleteTodo=(id)=>{setTodos(todos.filter(todo=>todo.id!==id));};return(<div className="todo-app"><input value={inputValue}onChange={(e)=>setInputValue(e.target.value)}onKeyPress={(e)=>e.key==="Enter"&&addTodo()}placeholder="Add a todo..."/><button onClick={addTodo}>Add</button><ul>{todos.map(todo=><li key={todo.id}className={todo.completed?"completed":""}><span onClick={()=>toggleTodo(todo.id)}>{todo.text}</span><button onClick={()=>deleteTodo(todo.id)}>Delete</button></li>)}</ul></div>);};
AFTER (Beautified JavaScript) 
const TodoApp = () => {
    const [todos, setTodos] = useState([]);
    const [inputValue, setInputValue] = useState("");
    
    const addTodo = () => {
        if (inputValue.trim()) {
            setTodos([
                ...todos,
                {
                    id: Date.now(),
                    text: inputValue,
                    completed: false
                }
            ]);
            setInputValue("");
        }
    };
    
    const toggleTodo = (id) => {
        setTodos(
            todos.map(todo =>
                todo.id === id
                    ? { ...todo, completed: !todo.completed }
                    : todo
            )
        );
    };
    
    const deleteTodo = (id) => {
        setTodos(todos.filter(todo => todo.id !== id));
    };
    
    return (
        <div className="todo-app">
            <input
                value={inputValue}
                onChange={(e) => setInputValue(e.target.value)}
                onKeyPress={(e) => e.key === "Enter" && addTodo()}
                placeholder="Add a todo..."
            />
            <button onClick={addTodo}>Add</button>
            <ul>
                {todos.map(todo => (
                    <li
                        key={todo.id}
                        className={todo.completed ? "completed" : ""}
                    >
                        <span onClick={() => toggleTodo(todo.id)}>
                            {todo.text}
                        </span>
                        <button onClick={() => deleteTodo(todo.id)}>
                            Delete
                        </button>
                    </li>
                ))}
            </ul>
        </div>
    );
};
Technical Features
  • AST-based parsing for safe and accurate formatting
  • Configurable indentation (2, 4, 8 spaces or tabs)
  • Smart bracket placement and alignment
  • Automatic semicolon insertion and removal
  • JSX/TSX formatting with proper attribute alignment
  • Comment preservation with intelligent repositioning
Professional Use Cases
Code Review & Collaboration
Standardize code formatting across team members
Legacy Code Maintenance
Improve readability of inherited or third-party code
Debugging Production Issues
Format minified code for easier troubleshooting
Documentation & Training
Create clean code examples for tutorials and guides
Code Quality Assurance
Ensure consistent formatting standards in projects
IDE Integration
Enhance development workflow with automated formatting
Best Practices
  • Establish consistent formatting rules across your entire development team
  • Integrate with ESLint and Prettier for automated code quality
  • Use format-on-save in your IDE for seamless development experience
  • Create configuration files for project-specific formatting standards
  • Format code before code reviews to focus on logic rather than style
  • Document your formatting conventions in project README files
Troubleshooting Guide
Parsing Errors
Check for syntax errors in the original code before formatting
Formatting Inconsistencies
Verify indentation settings and bracket placement rules
Large File Performance
Process very large files in smaller chunks or use streaming
JSX/React Issues
Ensure JSX mode is enabled for React component formatting
ES6+ Compatibility
Update parser settings to support latest JavaScript features