LibreOffice vs Office: PII Redaction

Two Suites, One Detection Engine

Updated for 2026. Teams often ask: does PII detection work the same way in LibreOffice and Microsoft Office?

With anonym.legal, it does. Both tools connect to the same backend. They share 267+ entity types and support for 48 languages. The only difference is how each platform installs — not what it detects.

Feature Comparison Table

Format Kept: Writer vs. Word

Both tools keep your text format when they replace PII. They use different APIs to do this.

LibreOffice Writer uses the UNO API. It keeps seven font traits: family, size, weight, style, color, underline, and strikethrough. It also keeps four paragraph traits: alignment, first-line indent, left margin, and right margin. Styles and tables stay in place.

Microsoft Word uses the Office.js API. It keeps font name, size, bold, italic, color, underline, strikethrough, and highlight. Paragraph alignment, indent, and line spacing are kept too. Tracked changes, headers, and footers stay in place.

The result is the same in both cases: PII is replaced, all other format stays intact.

Where the Two Differ

Platform coverage

The Office Add-in runs on Windows, macOS, the web, and iPad. The LibreOffice Extension runs on Windows, macOS, and Linux.

LibreOffice wins on Linux, where Microsoft's suite is not available. The Add-in wins on iPad and in browser-based work.

How to install

LibreOffice: Download the .oxt file. Double-click it to install. No admin approval is needed for personal use.

Office Add-in: Load it via a manifest URL. Or deploy it through the Microsoft 365 admin center. Enterprise teams use central admin controls.

Enterprise rollout

Microsoft 365 offers stronger enterprise tools: admin center deploy, Group Policy, and Intune. For LibreOffice, admins share the .oxt file through their own channels.

File format norms

Microsoft's suite is the norm in most corporate settings. LibreOffice is common in European public agencies and schools. Both can open each other's files. Each works best with its own format.

Consistent Results Across Both Platforms

The key benefit of using anonym.legal in both suites: detection results are the same.

Run the same text in Writer and in Word. The same entities appear. The same confidence scores show up. Presets sync across both. Encryption keys sync too.

This removes a real compliance risk. Many teams use one redaction tool for Word and a separate tool for LibreOffice. That creates gaps. See how presets prevent config drift for more detail.

When to Choose Which

Choose the LibreOffice Extension when:

• Your team runs LibreOffice
• You work on Linux
• Policy requires open-source software
• You want low-cost word processing with PII redaction built in

Choose the Office Add-in when:

• Your team uses Microsoft 365
• You need iPad or browser-based support
• You need enterprise rollout through the admin center
• Files must stay in .docx, .xlsx, or .pptx format

Use both when:

• Your setup is mixed — some teams use each suite
• You get files in both ODF and OOXML formats

Preset sync and shared encryption keys make switching between the two smooth.

Getting Started

• Download LibreOffice Extension — .oxt file, double-click install
• Install Office Add-in — Microsoft 365 integration
• See how it works in real Word documents — real-world cost example

Both use token-based pricing. Free tier: 200 tokens per month.

When This Approach Has Limits

Sharing one detection engine across both suites genuinely removes the cross-tool inconsistency that creates compliance gaps, and that shared-backend point is sound, but limits remain worth stating plainly.

Identical engines produce identical misses. The benefit of one backend is that Writer and Word return the same entities and the same confidence scores. The flip side is that a false negative in one is a false negative in both. Detection accuracy bounds the result everywhere: the regex and spaCy hybrid will miss the same unusual name or oddly formatted identifier regardless of which suite you run it in. Consistency across platforms is not the same as completeness, and a residual miss rate applies to both tools equally.

Format parity does not equal anonymization parity at the cell level. Both tools preserve fonts and paragraph traits in their word processor, but Calc and Excel do cell-based replacement without the same formatting model. More importantly, clearing direct identifiers from cells leaves quasi-identifiers in place. A combination of columns can re-identify someone even after names and emails are gone, so spreadsheet output is often pseudonymized rather than anonymized, with the legal weight that distinction carries.

Neither suite removes the human decision. Both require an account, an internet connection, and the same per-entity review step. Encryption keys sync zero-knowledge across platforms, which relocates rather than removes the key-custody burden: whoever holds the password holds the ability to reverse. The tools support compliance but do not constitute it. Choosing methods, confirming the preview, and judging whether a redaction meets the legal standard remain human responsibilities in both LibreOffice and Office alike.

Sources

• anonym.legal LibreOffice Extension docs — VERIFIED (feature parity confirmed in product)
• anonym.legal Office Add-in docs — VERIFIED (feature reference confirmed in product)
• GDPR Article 4(5) — data masking definition; Recital 26 — anonymization scope — VERIFIED-EXTERNAL