Ms Office Word Python

Microsoft Word — Python

Companion skill to ms-office-python (parent). For other areas see: ms-office-excel-python, ms-office-powerpoint-python, ms-office-graph-python, ms-office-enterprise-sso-python, ms-office-security-python.

Overview

.docx (Office Open XML, OOXML) is a zip of XML parts. Python can produce and consume it without Word installed using python-docx. Fidelity is a careful word here — see Library Selection for the caveats. Where actual Word is required (PDF render that matches Word's pagination exactly, complex field resolution, tracked-changes layout), the codepath is Windows/macOS-only and depends on a local Word install.

python-docx is the dominant library and remains actively maintained. The 2026 reality: it is enough for 80% of programmatic Word work, but it is NOT a full-fidelity Word renderer (see HARD-RULE-adjacent caveat below in Library Selection). For full fidelity, route through Word itself or LibreOffice headless.

Library Selection

Install Commands

RHEL 9 / AlmaLinux 9 / Rocky 9

sudo dnf install -y python3.12 python3-pip python3-devel gcc-c++ libxml2-devel libxslt-devel
python3 -m pip install --upgrade pip
python3 -m pip install python-docx docx2txt mammoth defusedxml
# Optional, for PDF / format conversion:
sudo dnf install -y libreoffice-core libreoffice-writer
python3 -m pip install pypandoc
# Optional, for legacy .doc:
sudo dnf install -y antiword

Debian 12 / Ubuntu 24.04

sudo apt update
sudo apt install -y python3.12 python3-pip python3-dev build-essential libxml2-dev libxslt1-dev
python3 -m pip install --upgrade pip
python3 -m pip install python-docx docx2txt mammoth defusedxml
sudo apt install -y libreoffice-core libreoffice-writer
python3 -m pip install pypandoc
sudo apt install -y antiword

Windows 11

winget install --id Python.Python.3.12 -e --silent
python -m pip install --upgrade pip
python -m pip install python-docx docx2txt mammoth defusedxml pypandoc
# Optional, requires Word installed:
#   python -m pip install docx2pdf pywin32
# Optional, headless conversion (no Word required):
#   winget install --id LibreOffice.LibreOffice -e --silent

Capability Matrix

Decision Sections

PDF generation

docx2pdf calls Word via COM internally and fails silently on Linux. Detect the OS and refuse to import docx2pdf on Linux to make the fallback path explicit.

Tracked changes and comments

python-docx exposes revisions through the underlying XML but does NOT model them as first-class objects. For programmatic tracked-changes workflows, the practical options are:

1. Convert .docx to HTML via mammoth and process the <ins> / <del> elements.
2. Use Word's COM API on Windows (pywin32) — flagged deprecated in the validator (E003) for new server code.
3. Round-trip through Word manually (the human user reviews / accepts / rejects).

If your workflow depends on tracked changes, the right choice in 2026 is to migrate the workflow to Word's native model + a server-side service that accepts the user-reviewed output — not to script the accept/reject in Python.

Macro-enabled documents (.docm)

python-docx.Document(path) accepts a .docm and reads its content, but on save it produces a .docx (no macros) or — if you rename — a .docm that has had word/vbaProject.bin stripped. This is HARD-RULE 1 above. Use the pre-flight detector in the rule to refuse silently-destructive round-trips.

If the workflow legitimately needs to preserve macros (rare; high-trust internal templates), the only path is live Word automation via pywin32 on a Windows machine.

Canonical Pattern (modified C3)

Read a .docx, modify a heading, write to a new file — most common Word task.

# CONFIDENCE: minimal viable pattern — production hardening notes in the Security Hardening section below; full references/ guide planned (v1.1).
from docx import Document

doc = Document("input.docx")
for paragraph in doc.paragraphs:
    if paragraph.style.name.startswith("Heading 1"):
        paragraph.text = paragraph.text.upper()  # in-place edit; preserves style
doc.save("output.docx")

This pattern enforces three things: read-then-write (no in-place mutation of the source), style-aware iteration (not naive string replace), no formula-injection / XXE concern because text is being set as-is via python-docx (which uses lxml internally — pin a known-good version).

Security Hardening

See ms-office-security-python for the consolidated checklist. Area-specific items:

• HARD-RULE 1: explicit user intent before any .docm round-trip.
• Pair python-docx with defusedxml. python-docx uses lxml internally; lxml has had multiple XXE CVEs. Pin the version and run pip-audit (delegate to dep-currency-check).
• For untrusted .docx input, parse in a sandboxed subprocess or container — billion-laughs and zip-bomb payloads are realistic.
• NEVER pass user-controlled paths to docx2pdf.convert — it spawns Word in the current user session; Word will follow any embedded INCLUDETEXT / INCLUDEPICTURE field, which can fetch from network. Strip fields before conversion if input is untrusted.
• Inspect doc.core_properties (author, last_modified_by, comments, keywords) before publishing externally — these carry PII and internal usernames.
• Workbook-style "embedded objects" in .docx (charts, OLE objects) can contain arbitrary file content. Enumerate doc.inline_shapes and doc.tables[].rows[].cells[].tables before declaring a document "safe."
• When converting Word to plaintext for downstream NLP / vector storage, strip embedded base64 images via docx2txt's img_dir mode and decide explicitly whether to retain them.
• For PDF generation on Linux via LibreOffice, run soffice with --norestore --nodefault --headless and a clean --env:UserInstallation=file:///tmp/lo-user-$$ to avoid lockfile contention in parallel CI runs.
• Audit log every .docx ingestion of a tracked / comment-bearing document — review-cycle metadata is sensitive.
• Refuse to process documents larger than a hard MAX_BYTES cap. Word documents over a few hundred MB are almost always pathological.

Selection Cheatsheet

• "Read a .docx into Python objects" → python-docx
• "Fast plaintext extraction" → docx2txt
• ".docx → HTML / Markdown" → mammoth
• ".docx → PDF on Linux/headless" → LibreOffice headless
• ".docx → PDF on Windows with Word installed" → docx2pdf
• "Convert between many doc formats" → pypandoc
• "Legacy .doc (Office 97-2003)" → LibreOffice headless OR antiword
• "Macro-preserving round-trip" → live Word via pywin32 (Windows only) OR refuse the workflow

Gotchas

• python-docx is NOT a full-fidelity Word renderer. Tracked changes, complex fields, comments, advanced layout do NOT round-trip losslessly. State this explicitly to users when designing a doc-modification pipeline.
• docx2pdf requires Word installed and is Windows/macOS only. It fails silently / cryptically on Linux. Detect OS and route around.
• python-docx strips macros from .docm on save — covered in HARD-RULE 1, repeated here because it bites.
• Word's auto-numbering (lists) is brittle through python-docx — round-tripping a heavily-numbered document loses numbering style continuity. Test before relying.
• LibreOffice headless contention: parallel runs share a profile dir by default and fail with "another OpenOffice.org process is running." Use --env:UserInstallation=file:///tmp/lo-user-$$ per process.
• pypandoc requires the pandoc binary on PATH — bundled pypandoc-binary is an alternative pip-installable form that ships a static pandoc.
• .docx files are zips. Some "broken" docs are actually zip-corrupted; zipfile.ZipFile(path).testzip() is a quick triage.

Update Triggers (per Codex M-1 — alf will scan these)

• Major version bump of: python-docx, mammoth, lxml, pypandoc, docx2pdf.
• New OOXML schema change announced by Microsoft.
• CVE published against lxml (XXE class) or python-docx.
• LibreOffice CLI flag changes (rare, but the soffice headless surface has churned historically).
• Annual review on: 2027-05-22.

See Also