turndown-py

A Python port of Turndown (v7.2.4), an HTML to Markdown converter originally written in JavaScript by Dom Christie.

Project Status

Conversion fidelity: 203 tests passing — 147 golden test cases ported from upstream (all match JS output), 39 internal/unit tests, 14 API tests.

• ✅ ruff check — clean
• ✅ ruff format — clean
• ✅ pytest tests/ — 203/203 passed

🎉 Additional tests in tests/test_internals.py:

• Pickle serialization — TurndownService round-trips through pickle.dumps/loads (required for Spark UDFs)
• Thread safety — 8 concurrent threads converting different HTML inputs produce correct, isolated results
• Statelessness — repeated calls with same input yield identical output
• Reference link isolation — per-call references state prevents cross-call contamination

Installation

pip install turndown-py

Requires Python 3.7+.

Development

# Clone and enter the repo
git clone https://github.com/M-Intelligence/turndown-py
cd turndown-py

# Create virtualenv and install dev dependencies
uv sync

# Run tests
uv run pytest

# Lint and format
uv run ruff check .
uv run ruff format .

Package Structure

Python Module	Ported From	Description
html_parser.py	html-parser.js	Pure-Python DOM tree via html.parser.HTMLParser with DomNode adapter providing JS-like childNodes, textContent, outerHTML, cloneNode(), getAttribute(), sibling traversal
utilities.py	utilities.js	Block/void element sets, escapeMarkdown(), extend(), repeat(), newline trimming helpers
collapse_whitespace.py	collapse-whitespace.js	DFS whitespace collapse preserving <pre> subtrees
node.py	node.js	annotate_node() — isBlock, isCode, isBlank, flankingWhitespace
rules.py	rules.js	Three-bucket rule system: forNode(), keep(), remove(), add()
commonmark_rules.py	commonmark-rules.js	All 15 CommonMark rules — paragraphs, headings, lists, code blocks, links, emphasis, images
root_node.py	root-node.js	Input normalization: parse HTML + collapse whitespace
service.py	turndown.js	TurndownService with full public API, pickle support, thread safety

Usage

from turndown import TurndownService

ts = TurndownService()
markdown = ts.turndown('<h1>Hello <em>world</em></h1>')
# => 'Hello _world_\n============='

License

GPL-3.0-or-later. The original turndown.js MIT license is retained in LICENSE_MIT. Attribution in CREDITS.