Why Use Our Online JavaScript Beautifier?

Production code is heavily minified (like Webpack or Terser bundles) to reduce load times, but this makes it impossible to debug. Our JavaScript formatter online safely restores logic flow, adding brackets, line breaks, and indentation without breaking execution.

Optimization FeatureTechnical ActionDeveloper Benefit
Unminify JS CodeParses dense, single-line script blocks and injects legal line breaks.Allows you to pretty print JS and debug third-party scripts.
ES6+ CompatibilitySafely handles Arrow Functions, async/await, and Promise chains.Formats modern JavaScript without breaking scope or execution context.
Smart IndentationAutomatically aligns nested callbacks, loops, and conditional statements.Makes it effortless to clean up messy scripts and find bugs.
Secure Local ExecutionRuns the entire AST parser 100% inside your web browser.Zero server uploads ensure your proprietary algorithms stay private.

Live Examples: Unminify & Format JS Online

Watch how our tool transforms dense, compiled application bundles into perfectly readable logic.

Example 1: Unminify Production JS

When you pull a script from a production bundle, variable names might be mangled and lines collapsed. Click below to expand it.

Minified Input
function calculateTotal(e,t,n){let r=0;for(let o=0;o<e.length;o++){r+=e[o].price*e[o].qty}return r>t?r-=n:r,r}
Formatted Output
function calculateTotal(e, t, n) {
    let r = 0;
    for (let o = 0; o < e.length; o++) {
        r += e[o].price * e[o].qty
    }
    return r > t ? r -= n : r, r
}

Example 2: Formatting ES6 Promises & Fetch

Modern syntax like Async/Await and Arrow functions can get messy fast. Our beautifier handles nested ES6 logic flawlessly.

Compressed ES6 Input
const fetchData=async(url)=>{try{const res=await fetch(url);...}
Structured Output
const fetchData = async (url) => {
    try {
        const res = await fetch(url);
        const data = await res.json();
        return data.filter(i => i.active)
    } catch (e) {
        console.error(e)
    }
};

Frequently Asked Questions

What is an online JavaScript formatter?

An online JavaScript formatter (or JS beautifier) is a developer tool that takes compressed, minified, or obfuscated JavaScript code and applies proper indentation, line breaks, and spacing. It transforms dense production scripts into human-readable code, making it significantly easier for developers to debug logic flows.

How to unminify JavaScript code securely?

To unminify JavaScript code securely, paste your minified script into our editor. Our system uses a powerful client-side engine to instantly pretty print JS. Because the formatting runs 100% inside your web browser locally, your proprietary business logic and algorithms are never uploaded to any remote server.

Does this JS beautifier support modern ES6+ syntax?

Yes. Our advanced JavaScript beautifier perfectly parses and formats modern syntax, including ES6+ arrow functions, async/await blocks, destructuring assignments, and complex Promise chains. It ensures that your logic is accurately indented without breaking variable scopes.