Python to JavaScript Converter
Port Python backend logic to JavaScript for web and Node.js applications. AI-powered conversion transforms Python asyncio to JavaScript Promises, list comprehensions to Array methods, and dataclasses to ES6 classes. Handles Flask routes to Express, Django models to Sequelize ORM, and Python decorators to JavaScript higher-order functions automatically.
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Issue Description
Hint: Describe what you want to build or paste requirements, select target language, and click Generate.
How It Works
- Step 1: Paste your Python source code including async/await functions, class definitions with decorators, list comprehensions, and module imports.
- Step 2: The AI analyzes Python-specific patterns like context managers (with statements), multiple inheritance, generator expressions, and dictionary comprehensions.
- Step 3: Advanced models transform Python idioms to JavaScript equivalents—asyncio becomes Promises, f-strings convert to template literals, and type hints guide JSDoc generation.
- Step 4: Receive modern ES6+ JavaScript code with async/await, classes, arrow functions, and proper error handling ready for browser or Node.js deployment.
Python vs JavaScript: Language Comparison
| Feature | Python | JavaScript |
|---|---|---|
| Syntax Style | Indentation-based | Brace-delimited with semicolons |
| Type System | Dynamic, strongly typed | Dynamic, weakly typed |
| Async Model | asyncio coroutines | Promises, async/await |
| Concurrency | asyncio, threading, GIL | Single-threaded event loop |
| Package Management | pip, poetry, conda | npm, yarn, pnpm |
Code Conversion Examples
Example 1: List Comprehensions to Array Methods
def process_numbers(numbers):
squared = [n ** 2 for n in numbers if n > 5]
names = [f"Number {n}" for n in squared]
total = sum(squared)
return {
'squared': squared,
'names': names,
'total': total
}
# Usage
result = process_numbers([3, 7, 2, 9, 12, 5])
print(result['total'])function processNumbers(numbers) {
const squared = numbers
.filter(n => n > 5)
.map(n => n ** 2);
const names = squared.map(n => 'Number ' + n);
const total = squared.reduce((acc, n) => acc + n, 0);
return {
squared: squared,
names: names,
total: total
};
}
// Usage
const result = processNumbers([3, 7, 2, 9, 12, 5]);
console.log(result.total);Key Changes:
Python list comprehensions with filtering convert to JavaScript's filter().map() chaining. F-strings become template literals with backticks. The sum() built-in transforms to reduce() with an accumulator. Dictionary literals map to object literals. Print statements become console.log() calls.
Example 2: Async/Await and Context Managers
import asyncio
import aiohttp
from contextlib import asynccontextmanager
@asynccontextmanager
async def get_session():
session = aiohttp.ClientSession()
try:
yield session
finally:
await session.close()
async def fetch_data(url):
async with get_session() as session:
async with session.get(url) as response:
data = await response.json()
return [item for item in data if item['active']]
# Usage
result = await fetch_data('https://api.example.com/users')const axios = require('axios');
async function getSession() {
const session = axios.create();
return {
session,
close: async () => { /* cleanup */ }
};
}
async function fetchData(url) {
const { session, close } = await getSession();
try {
const response = await session.get(url);
const data = response.data;
return data.filter(item => item.active);
} finally {
await close();
}
}
// Usage
const result = await fetchData('https://api.example.com/users');Key Changes:
Python's asynccontextmanager decorator converts to a JavaScript factory function with explicit cleanup. The 'async with' pattern becomes try-finally blocks ensuring resource cleanup. List comprehensions with filtering translate to Array.filter(). The aiohttp library maps to axios or fetch API in JavaScript, maintaining async/await patterns throughout.
Frequently Asked Questions
Can I configure how Python list comprehensions map to JavaScript?
The converter generates JavaScript Array methods (map, filter, reduce) or for-of loops from Python list comprehensions by default. Complex nested comprehensions may produce verbose code. Advanced users can manually replace with lodash chains post-conversion. The tool prioritizes readability over conciseness.
Is my Python code sent to external servers for conversion?
Yes. AI conversion requires server-side LLM processing. Your Python source is transmitted over HTTPS to our API, converted by language models, then discarded. We do not store code or train models on submissions. Review data policies before converting proprietary code.
What Python features have no JavaScript equivalent?
Python's multiple inheritance, operator overloading (__add__, __eq__), and context managers (with statement) lack direct JavaScript mappings. Decorators with arguments require manual factory function conversion. The tool excels at standard Python but struggles with metaprogramming (metaclasses, descriptors).