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LibreOffice vs Office: PII Redaction

Detailed comparison of PII anonymization capabilities in LibreOffice (anonym.legal extension) vs. Microsoft Office (Office Add-in).

March 10, 20268 minute read
LibreOffice extensionOffice Add-in comparisondocument redactionPII tool comparisonopen source privacy

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 285+ entity types and support for 48 languages. The only difference is how each platform installs — not what it detects.

Feature Comparison Table

FeatureLibreOffice ExtensionOffice Add-in
Detection enginePresidio hybrid (regex + spaCy NLP)Presidio hybrid (regex + spaCy NLP)
Entity types285+285+
Languages4848
MethodsReplace, Mask, Redact, Hash, EncryptReplace, Mask, Redact, Hash, Encrypt
Word processingWriter (format kept)Word (format kept)
SpreadsheetsCalc (cell-based)Excel (cell-based)
PresentationsImpress (text objects)PowerPoint (text objects)
PreviewUp to 50 entitiesUp to 50 entities
Per-entity controlsYesYes
PresetsYes (synced)Yes (synced)
Encryption keysZK-wrapped, syncedZK-wrapped, synced
LoginZK (Argon2id)ZK (Argon2id)
PlatformsWindows, macOS, LinuxWindows, macOS, Web, iPad
File type.oxt fileAdd-in manifest
Offline modeNo (API needed)No (API needed)
CostSame token pricingSame token pricing

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

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

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

Ready to protect your data?

Start anonymizing PII with 285+ entity types across 48 languages.

About this page

We update this page when our platform or the law changes.

Read our founder note for how we work.

Each change shows up in the timestamp at the top.

Related reading

We follow these rules

  • GDPR (EU 2016/679).
  • ISO/IEC 27001:2022.
  • NIS2 (EU 2022/2555).
  • HIPAA safe harbor under 45 CFR § 164.514(b)(2).

Our promise

We do not sell your data.

We do not train models on your text.

We store your files in Germany.

You can delete your account at any time.

You own your work.

Where we run

Our servers live in Falkenstein, Germany.

We use Hetzner. They hold ISO 27001 certification.

All data stays in the EU.

Backups run every day.

Need help?

Email support@anonym.legal.

We reply within one business day.

How we test

We run a full check suite on every release.

Each surface gets its own sweep script and report.

Human reviewers spot-check the output each week.

We track recall and precision on a labelled set.

Bad runs block the deploy.

What we never do

  • We never sell your information to third parties.
  • We never train models on what you upload.
  • We never keep your work after you delete it.
  • We never share keys with any outside firm.
  • We never run ads inside the product.

Plans in plain words

We sell credits, not seats.

One credit covers one short job.

Long jobs use a few credits each.

You can top up at any time.

Unused credits roll over each month.

Read the plans page for current rates.

Who built this

A small team of engineers and lawyers built this.

We ship from Europe and work in the open.

Our founder note spells out why we started.

Where to start

How the parts fit

A browser add-on cleans text inside Chrome.

A Word plug-in handles drafts in Office.

A small desktop tool works on whole folders.

An agent protocol link feeds large models safely.

All four share one core engine and one rule set.

Words from our team

We started this work after a lunch about cookies.

One friend kept getting odd ads on her phone.

We asked why a court file leaked through a draft.

We sketched the first build on a napkin that week.

By month three we had a tiny demo for a friend.

She used it on her first case the next day.

Common questions we hear

Can the tool read scanned PDFs? Yes, with OCR.

Does it work on long files? Yes, in small chunks.

Can I roll my own rule set? Yes, save it as a preset.

Does it run offline? The desktop build runs offline.

Do you keep my files? No, the cloud build wipes after each run.

Will it learn from my work? No, we never train on inputs.

A short tour of the workflow

Upload a file or paste a snippet of prose.

Pick the entities you want gone from the draft.

Choose a method: replace, mask, hash, encrypt, or redact.

Press run and watch the side panel show each hit.

Skim the result and tweak any rule that misfired.

Save the cleaned file or send it to a teammate.