Introducing PyScript: Running Python Directly in the Browser for Frontend Development

As a Python programmer who admires JavaScript developers for their ability to create impressive web pages, I introduce PyScript—a tool that lets you write and run Python directly in the browser, effectively enabling full‑stack development with Python.

What Is PyScript

PyScript is a JavaScript library created by the Anaconda team that allows Python code to be embedded inside HTML tags and executed client‑side without any server.

How It Works

PyScript is built on Pyodide , a WebAssembly/Emscripten port of CPython, which brings the full Python runtime to the browser.

It currently supports Python in the browser and plans to support additional languages in the future.

Benefits of PyScript

Enables more front‑end developers to use Python.

Lowers the programming barrier since a web browser is all that’s needed—no extra software installation.

Eliminates deployment concerns; everything runs directly in the browser.

How to Use PyScript

Three main components are used in an HTML file:

py-env – defines the packages required for the Python code.

py-script – the place where you write Python code in the page.

py-repl – creates a REPL component to evaluate user input and display results.

Example todo.html demonstrates the use of <py-env> and <py-script> tags:

Running the demo shows the Python code executing inside the page.

Another example using repl demonstrates an interactive Python REPL embedded in the browser:

Running the Demos

git clone https://github.com/pyscript/pyscript.git
cd pyscript
npm install 
npm run dev

Then open http://localhost:8080 in a browser to see the interface.

Future of PyScript

Bringing Python to the browser is a valuable innovation; with over 2.7K GitHub stars, PyScript shows strong community interest and potential for building full web applications.

Conclusion

This article introduced the 2022‑released PyScript technology; if you find it useful, consider sharing it.