By George Curta · Last updated 2026-05-28
anonym.legal vs Philter
Philter (Philterd) is an open-source PII/PHI redaction tool with 30+ entity types and self-hosting capabilities. anonym.legal is a managed PII anonymization platform with reversible encryption, 285+ entity types, and user-level tools for transforming data before sharing with AI.
Learn more about Philter
Feature Comparison
| Feature | anonym.legal | Philter |
|---|---|---|
| PII Detection | Yes | Check |
| PII Redaction | Yes | Check |
| Reversible Encryption | AES-256-GCM | Not found |
| Entity Types | 285+ | 30+ |
| Languages Supported | Yes | Not documented |
| Self-Hosted Option | No | Check |
| Managed Service | Yes | DIY |
| REST API | Yes | Not documented |
| MCP Server | Yes | Not found |
| Chrome Extension | Yes | Not found |
| Office Add-in | Yes | Not found |
| Desktop App | Yes | Not found |
| Open Source | Yes | Check |
| Starting Price | Free / €3/mo | Free (self-hosted) |
| Zero-Knowledge Auth | Yes | Not found |
Comparison based on publicly available information. "Not found" indicates feature not documented on product page. Last updated February 2026.
Why Choose anonym.legal
97% Lower Cost
Start at €3/month instead of $800/month. Free tier available with no credit card required.
Reversible Encryption
Unique AES-256-GCM encryption that can be decrypted when needed. Essential for legal discovery.
AI Chat Protection
Chrome Extension protects data before it reaches ChatGPT, Claude, or Gemini.
MCP Server
Integrate with Claude Desktop, Cursor, and other AI tools via Model Context Protocol.
48 Languages
Full support for 48 languages including RTL. Compare entity detection across regions.
EU Data Residency
All data processed on ISO 27001-certified servers in Germany. No US jurisdiction concerns.
When Philter Might Be Better
Philter excels in self-hosted scenarios:
- Full control over infrastructure
- Open-source code inspection
- Air-gapped or isolated environments
- Custom modifications to detection logic
- Zero external dependencies
Frequently Asked Questions
What is the main difference between Philter and anonym.legal?
Philter is an open-source, self-hosted PII redaction library with 30+ entity types. anonym.legal is a managed service with 285+ entity types, reversible encryption, and end-user tools like Chrome Extension and Office Add-in.
Is Philter truly free?
Philter is open source but requires infrastructure costs and DevOps expertise to deploy and maintain. anonym.legal has a free tier with managed infrastructure.
Does Philter support reversible encryption?
Reversible encryption is not documented in Philter's public documentation. anonym.legal offers AES-256-GCM reversible encryption to restore original values.
Which has better entity coverage?
anonym.legal detects 285+ entity types across 48 languages. Philter documents 30+ entity types (PII/PHI/NPPI) with undocumented language support.
Can end users work with Philter directly?
Philter is a developer library without end-user interfaces. anonym.legal provides Chrome Extension, Office Add-in, and Desktop App for non-technical users.
Does anonym.legal offer zero-knowledge authentication?
Yes. anonym.legal uses zero-knowledge authentication with Argon2id and HKDF. Your password is processed on your device — only a mathematical proof is sent to the server, never the actual password.
Try anonym.legal Free
Start protecting sensitive data today with 285+ entity types, 48 languages, and reversible encryption.
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
- Common questions
- Glossary
- How tokens work
- Security posture
- Where we comply
- What we detect
- Case studies
- Release notes
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
- Open the web app and try a sample file.
- Learn how credits get counted.
- See current plans and limits.
- Meet the team behind the product.
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.