Open Source

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.

Feature Comparison

Featureanonym.legalPhilter
PII DetectionYesCheck
PII RedactionYesCheck
Reversible EncryptionAES-256-GCMNot found
Entity Types285+30+
Languages SupportedYesNot documented
Self-Hosted OptionNoCheck
Managed ServiceYesDIY
REST APIYesNot documented
MCP ServerYesNot found
Chrome ExtensionYesNot found
Office Add-inYesNot found
Desktop AppYesNot found
Open SourceYesCheck
Starting PriceFree / €3/moFree (self-hosted)
Zero-Knowledge AuthYesNot 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.