PYTML - Python in Your Browser

Run Python in your browser with zero configuration — no server, just a script tag.

Pytml 2.5 is a lightweight JavaScript bridge built on Pyodide 0.314.0.7. Write Python inside HTML, interact with ordinary DOM elements, and use the small numbered UI syntax supported by the 2.5 runtime.

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Quick Start

Add one line to your HTML:

<script src="https://pytml.vercel.app/pytml.js"></script>

Then write Python:

<py>
print("Hello, world!")
name = input("Your name? ")
print(f"Hi {name}!")
</py>

Pytml 2.5 UI Syntax

Inside a <pyN> block, Pytml 2.5 recognizes numbered UI tags such as:

<py1>

<btn1>1</btn1>
<btn2>2</btn2>
<txt1>

def show(e):
    print("You clicked a button")

btn1.on("click", show)

</py1>

<btnN> becomes a real <button id="btnN">, while <inputN> and <txtN> become real text inputs. Python indentation is preserved before the source is passed to Pyodide.

Normal HTML + Python

Ordinary HTML IDs are available to Python:

<button id="hello">Click me</button>
<p id="result"></p>

<py>
def hello(event):
    result.text = "Hello from Python!"

hello.on("click", hello)
</py>

Packages

Pytml keeps the Pyodide package workflow, including micropip:

import micropip
await micropip.install("numpy")

import numpy as np
print(np.mean([1, 2, 3]))

Packages available in the Pyodide environment can be used from Pytml, including common scientific packages such as NumPy, pandas and Matplotlib.

Multiple Programs

<py1>, <py2>, <py3>, and so on are identifiers, not filenames. Blocks with the same identifier belong to the same program:

<py1>
x = 10
</py1>

<py1>
print(x)
</py1>

<py2>
print("Another program")
</py2>

Local Files

Pytml supports local HTML files opened directly with file:// when the Python code is inline:

<script src="https://pytml.vercel.app/pytml.js"></script>

<py>
print("Hello from a local file!")
</py>

No Python web server is required for this case. You can also use a local copy of pytml.js with file:// by changing the script source to ./pytml.js.

A relative external Python file such as <py src="app.py"> cannot be fetched from file:// by normal browser JavaScript because of browser security restrictions; use inline Python or an HTTPS Python source URL for that case.

See local-file-test.html for a ready-to-open example.

Features

• Zero config — one script tag
• Python in HTML
• DOM interaction
• Browser input()
• Numbered inline UI controls
• Mouse, pointer, touch, keyboard and scroll events
• Joystick and gamepad helpers
• Canvas, audio and video helpers
• Clipboard, storage, downloads and fullscreen helpers
• Package support through micropip
• NumPy, pandas and Matplotlib support through the Pyodide environment
• Privacy-first client-side execution

Links

Official Website → https://pytml.js.org/

Demos → https://pytml.js.org/demo.html

GitHub → https://github.com/NodeX-AR/Pytml

License

Pytml is open-source under the Apache 2.0 License.

Support

If you find Pytml useful, consider giving it a star on GitHub!