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Python to JavaScript Converter

Python to JavaScript Converter

Translate a subset of Python (print, if/for/while, def, f-strings, lists) into JavaScript.

Python

client-side
simple subset
no network

Supported: print, assignments, if/elif/else, for (range & iterables), while, def, return, f-strings, len/append, and comments. Classes, exceptions, and imports are emitted as comments — always review the result.

Examples

FizzBuzz from Python to JavaScript

Input
for i in range(1, 16):
    if i % 15 == 0:
        print("FizzBuzz")
    elif i % 3 == 0:
        print("Fizz")
    elif i % 5 == 0:
        print("Buzz")
    else:
        print(i)
Output
for (let i = 1; i < 16; i++) {
  if (i % 15 === 0) {
    console.log("FizzBuzz");
  } else if (i % 3 === 0) {
    console.log("Fizz");
  } else if (i % 5 === 0) {
    console.log("Buzz");
  } else {
    console.log(i);
  }
}

range() becomes a C-style for loop, print becomes console.log, and Python's indentation becomes brace-delimited blocks.

About this tool

The Python to JavaScript Converter reads simple Python scripts and rewrites them as JavaScript, covering the constructs that make up most short scripts: print becomes console.log, def becomes function, indentation-based blocks become braces, for-in-range becomes a classic C-style for loop, and f-strings become template literals. It also maps True/False/None, and/or/not, len, and list.append to their JavaScript equivalents.

It targets a deliberate subset — classes, exceptions, and imports are not translated; they are emitted as comments with a warning, and you should always review the output for anything beyond basic scripts. The translator runs entirely in your browser, so your code never leaves your machine and there is no signup. Use it to port a quick algorithm, explain Python to a JavaScript developer, or bootstrap a translation that you then finish by hand.

How to use

  1. Paste a Python script

    Paste code built from the supported subset — print, if/elif/else, for and while, def, f-strings, and lists.

  2. Read the translated JavaScript

    Inspect the output as it appears: console.log calls, C-style for loops, template literals, and braced blocks.

  3. Review and finish by hand

    Handle skipped constructs (classes, exceptions, imports) left as comments and adjust the result to your codebase.

Use cases

Port a quick algorithm

Translate a short solution (sorting, FizzBuzz, math helpers) you found in Python into a runnable JavaScript equivalent fast.

Explain Python to a JS developer

Show one-to-one mappings — def → function, print → console.log, f-strings → template literals — side by side.

Bootstrap a migration

Start a larger port from translated output and finish the classes, exceptions, and imports by hand.

Common mistakes

Mistake:Feeding in classes, exceptions, or imports.

Fix:Those constructs are deliberately skipped and emitted as comments with warnings — keep them out of the input or plan to rewrite them by hand.

Mistake:Trusting the output without reviewing it.

Fix:Treat the result as a strong starting point; always read the translated code before shipping it, especially beyond basic control flow.

Mistake:Expecting exact Python semantics.

Fix:print's sep/end, list methods beyond append, and slicing are not part of the subset — verify that behavior matters to your script.

Frequently asked questions

References & standards