ES5 to ES6+ Converter

Modernize your JavaScript code with ES6+ features

ES5 Input

Loading editor...

ES6+ Output

ES6+ code will appear here

Paste ES5 code in the input area

How to Convert ES5 to ES6+ - Step by Step Guide

Step 1

Input Your ES5 Code

Let's modernize your legacy ES5 code to ES6+! You have several options:

Paste directly: Copy your ES5 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 conversion examples

Example: ES5 Code Input

Here's legacy ES5 JavaScript:

var numbers = [1, 2, 3];
var doubled = numbers.map(function(n) {
  return n * 2;
});
Step 2

Automatic Modern Syntax Conversion

The converter modernizes your code instantly! It automatically applies:

Arrow functions: Converts function expressions to concise arrow functions
Let and const: Replaces var with appropriate let or const declarations
Template literals: Updates string concatenation to template strings

Example: Modern ES6+ Output

The same code with modern syntax:

const numbers = [1, 2, 3];
const doubled = numbers.map((n) => n * 2);
Step 3

Review Modern Features

Check the modernized code with ES6+ features:

Cleaner syntax: More concise and readable code
Better scoping: Block-level scoping with let and const
Modern patterns: Uses current JavaScript best practices
Step 4

Export Modern Code

Save your modernized JavaScript:

Copy to clipboard: One-click copying for your project
Download as file: Save as a .js file with modern syntax
Ready to use: Compatible with modern browsers and Node.js

Frequently Asked Questions

What ES6+ features does this converter add?

The converter adds arrow functions, let/const declarations, template literals, destructuring, spread operators, and other modern JavaScript features where applicable. It analyzes your ES5 code and applies appropriate ES6+ syntax.

Will converted code work in all browsers?

ES6+ features work in all modern browsers. For older browser support, use transpilation tools like Babel to convert ES6+ back to ES5. Most modern projects target recent browsers that fully support ES6+.

Why should I modernize ES5 to ES6+?

Modern ES6+ syntax is more concise, readable, and follows current best practices. It provides better variable scoping, cleaner function syntax, and improved string handling. Modernizing code makes it easier to maintain and understand.

Does conversion change code behavior?

No, the conversion preserves code functionality. Arrow functions and let/const have some scoping differences from their ES5 counterparts, but the converter applies them appropriately. Always test converted code to ensure it works as expected.

Can I convert ES6+ back to ES5?

Yes, use transpilers like Babel or our JavaScript Transpiler to convert ES6+ features back to ES5 for compatibility with older environments. This is common in production builds targeting wider browser support.

Is the ES5 to ES6 converter completely free?

Yes, totally free with no limitations on file size or usage frequency. No registration required, and you can modernize unlimited JavaScript files to ES6+ syntax.