---
id: pscript
version: "0.8.1"
license: unclear
license_treatment: unclear
maintenance: active
---

# pscript — Python to JavaScript compiler.

License: unclear · Maintenance: active · Downloads: 284.7K/mo

## What it is and what it does

PScript is a Python-to-JavaScript compiler that translates a carefully defined subset of Python into executable JavaScript. It was originally built as part of the Flexx framework and now stands as a standalone tool. The compiler takes Python functions and classes and outputs equivalent JavaScript code, allowing developers to write browser-facing code using Python syntax and semantics.

The package is pure Python with no external dependencies, making installation trivial. It targets modern browsers (Firefox, Chrome, Edge) and Internet Explorer 9 and above, though some newer Python constructs like async/await do not work in older browsers. The generated JavaScript handles Python-specific features like default arguments and prints to the browser console. It is actively maintained and used in production projects like TimeTagger.app.

Use it for:

- Build interactive web frontends where you want to write client-side logic in Python rather than JavaScript.
- Compile Python functions to JavaScript for use in web applications or browser-based tools.
- Develop Flexx-based applications that automatically transpile Python UI code to run in the browser.
- Create hybrid Python/JavaScript projects where business logic can be shared or ported between server and client.
- Prototype browser interactions and DOM manipulation using Python syntax before or instead of learning JavaScript.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

PScript compiles a Python subset to JavaScript, enabling you to write browser-facing code in Python syntax instead of JavaScript.

Yes, if you need to write browser code in Python. The package has no dependencies, installs cleanly, is actively maintained, and solves a real problem for teams that prefer Python syntax. The main gotcha is that only a Python subset compiles—you need to verify your code will translate before committing to this approach.

## Install

pip install pscript
uv add pscript
poetry add pscript

## Installing pscript

Before you install: Installation is straightforward: the package is pure Python with no runtime dependencies, distributed as a wheel, and requires Python 3.8 or later. The project is actively maintained with a recent release.

Quickstart:

from pscript import py2js

def foo(a, b=2):
    print(a - b)

print(py2js(foo))

Requires Python 3.8 or later; only a subset of Python syntax is supported (not all Python features compile to JavaScript).

Verify before relying:

- Exact scope of Python subset supported (which language features compile and which do not)
- Performance characteristics of generated JavaScript compared to hand-written code
- Browser compatibility details beyond the stated modern-browser and IE9+ support

## Package facts

- License: not declared (unclear)
- Python support: supports_current
- Install friction: low
- Maintenance: active
- Downloads: 284.7K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

python to javascript compiler, python javascript transpiler, write javascript in python, python browser code, python js compiler, cross-language transpilation, client-side python, transpiler, web-dev

[View on SkillFed](https://skillfed.io/packages/pscript) · [View on PyPI](https://pypi.org/project/pscript/)