JavaScript Transpiler

Convert modern JavaScript to browser-compatible code

Modern JavaScript Input

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Transpiled Output

Transpiled code will appear here

Paste modern JavaScript in the input area

How to Transpile JavaScript - Step by Step Guide

Step 1

Input Your Modern JavaScript

Let's transpile your modern JavaScript to ES5 for compatibility! You have several options:

Paste directly: Copy your ES6+ JavaScript and paste it into the input editor
Upload a file: Click "Upload" to select a .js file from your computer
Try the sample: Click "Sample" to see transpilation in action

Example: Modern ES6+ Input

Here's modern JavaScript with ES6+ features:

const greet = (name) => Hello, ${name}!;
const {age, city} = { age: 25, city: "NYC" };
Step 2

Automatic ES5 Transformation

The transpiler converts modern syntax instantly! It automatically transforms:

Arrow functions: Converts to traditional function expressions
Template literals: Replaces with string concatenation
Destructuring and more: Transpiles all ES6+ features to ES5 equivalents

Example: Transpiled ES5 Output

The same code transpiled to ES5:

var greet = function(name) {
  return "Hello, " + name + "!";
};
var age = 25;
var city = "NYC";
Step 3

Verify Browser Compatibility

The transpiled code works in all browsers:

ES5 compatible: Works in Internet Explorer 11 and all modern browsers
Same functionality: Behavior is preserved, just with older syntax
Production ready: Safe to deploy to production environments
Step 4

Export Transpiled Code

Get your browser-compatible JavaScript:

Copy to clipboard: One-click copying for deployment
Download as file: Save transpiled code as a .js file
Universal compatibility: Works across all JavaScript environments

Frequently Asked Questions

What is JavaScript transpilation?

Transpilation is the process of converting modern JavaScript (ES6+) to older JavaScript (ES5) that works in all browsers, including older ones. It allows developers to write modern code while maintaining broad compatibility.

When should I transpile JavaScript?

Transpile when you need to support older browsers like Internet Explorer or older versions of mobile browsers. If you're targeting only modern browsers, you can skip transpilation and use native ES6+ features.

Does transpilation affect performance?

Transpiled code may be slightly larger and sometimes less efficient than native ES6+ code. However, the performance difference is usually negligible, and transpilation ensures your code works everywhere. Consider using compression for production.

What features can be transpiled?

Most ES6+ features can be transpiled including arrow functions, template literals, destructuring, classes, modules, async/await, and more. Some newer features may require polyfills for full functionality in older browsers.

Should I transpile for Node.js?

Modern Node.js versions (12+) support most ES6+ features natively. Transpilation for Node.js is usually unnecessary unless you're targeting older Node versions or need specific advanced features not yet implemented.

Is the JavaScript transpiler completely free?

Yes, totally free with no limitations on file size or usage frequency. No registration required, and you can transpile unlimited JavaScript files for maximum browser compatibility.