Brython

Spec sheet

Purpose

Brython implements Python 3 in the browser and lets developers run Python code in HTML pages.Read 8 Oct 2026 · brython.info

Deployment

A Brython application can be deployed by uploading its directory to a server or packaged for distribution through PyPI.Read 8 Oct 2026 · brython.info

Integrations

A CPython package installed with pip can be added to a Brython application with brython-cli add_package.Read 8 Oct 2026 · brython.info

Async programming

The CPython asyncio module is not usable in Brython; the documentation provides the Brython-specific browser.aio module instead.Read 8 Oct 2026 · brython.info

Browser features

Its examples cover creating and modifying page elements, events, graphics, animations, Ajax requests, and local file selection.Read 8 Oct 2026 · brython.info

Browser file limits

The browser environment prevents file writing, and file reading is limited to files accessible through Ajax requests.Read 8 Oct 2026 · brython.info

Browser support

The FAQ says Brython supports all modern browsers, including browsers on smartphones.Read 8 Oct 2026 · brython.info

Distribution

Brython packages bundle importable modules in .brython.js files that can be hosted on any server.Read 8 Oct 2026 · brython.info

DOM interface

Brython provides browser-facing modules for working with the DOM, including document and window.Read 8 Oct 2026 · brython.info

DOM support

Brython provides access to browser pages through the DOM using the browser module's document and window objects.Read 8 Oct 2026 · brython.info

File access limits

Browser file access is constrained: writing is impossible through the documented Python file interface, and reading is limited to files reachable by Ajax requests.Read 8 Oct 2026 · brython.info

HTML elements

The browser.html module exposes HTML4, HTML5, and some HTML5.1 tags as Python classes.Read 8 Oct 2026 · brython.info

Install options

Brython can be loaded from jsDelivr or cdnjs without installation, or installed locally with pip or a downloadable release.Read 8 Oct 2026 · brython.info

Installation

Brython can be used from jsDelivr or cdnjs without installation, or installed locally with pip or a GitHub release archive.Read 8 Oct 2026 · brython.info

JavaScript interoperability

Brython provides ways for Python code to use JavaScript objects and libraries.Read 8 Oct 2026 · brython.info

Network limitations

Browser code can make Ajax requests to its own domain and to sites that support cross-origin requests; the FAQ gives requests as an incompatible example.Read 8 Oct 2026 · brython.info

Package limitations

The FAQ says Brython cannot use CPython packages that rely on C extensions, naming NumPy, Matplotlib, and Pandas as examples.Read 8 Oct 2026 · brython.info

Package limits

Brython runs Python programs, not programs written in C, so numpy and data science packages that rely on it will not work.Read 8 Oct 2026 · brython.info

Python syntax

Brython supports the keywords and functions of the corresponding Python version, subject to browser and JavaScript limitations.Read 8 Oct 2026 · brython.info

Security and compliance

The official pages reviewed provide no stated security certification or compliance claim.Read 8 Oct 2026 · brython.info

Security constraints

Browser restrictions limit HTTP requests; packages such as requests and urllib.request cannot send arbitrary requests to any URL.Read 8 Oct 2026 · brython.info

Supported library

Brython includes part of the CPython standard library and can install compatible Python packages, but packages containing C-written files are excluded.Read 8 Oct 2026 · brython.info

Where Specifiction places it

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