How anonym.legal Works
Regex patterns for structured data deliver 100% reproducible results. Proven ML models for names provide high accuracy. Transparent, auditable detection you can trust.
How Does PII Detection Work?
PII detection identifies personal data in text using pattern matching and machine learning. anonym.legal uses a hybrid approach:
- 1Pattern Matching: Regex patterns detect structured data (SSNs, credit cards, IBANs) with checksum validation.
- 2Named Entity Recognition: NER models identify names, locations, and organizations in 48 languages.
- 3Context Scoring: Each detection is scored based on surrounding context to minimize false positives.
This hybrid approach detects 285+ entity types while maintaining deterministic, reproducible results — essential for compliance and legal discovery.
Our Hybrid Approach
How We Detect PII
- Regex patterns for structured data (emails, SSNs, credit cards)
- Proven ML models for names and organizations
- 100% reproducible regex results
- High accuracy ML detection
- Fully auditable for compliance
- Transparent confidence scoring
Pure AI-Only Approach
- Inconsistent results across runs
- Black-box decision making
- Hallucination risks with LLMs
- High compute costs per request
- Difficult to audit or explain
- May miss structured patterns
The 10-Step Process
From input to output, here's exactly what happens to your document
Input Text
Submit your document via web interface, API, or Office Add-in
Language Detection
System identifies the document language for optimal processing
Tokenization
Text is broken into tokens for pattern matching
Pattern Matching
Regex patterns scan for 285+ entity types
Context Analysis
Surrounding text improves detection accuracy
Confidence Scoring
Each detection receives a confidence score
Entity Classification
Detected items are categorized by type
Review Results
See all detections with positions and scores
Apply Anonymization
Choose your method: Replace, Redact, Hash, Encrypt, or Mask
Output Document
Download your anonymized document
MCP Server: Privacy-First AI Integration
How your data flows through the MCP Server to keep AI tools safe
AI Tool Request
Your AI tool (Cursor, Claude) sends a request containing PII
MCP Server Intercepts
Server analyzes and detects all PII entities
Anonymization
PII is replaced with tokens or redacted
AI Processing
AI receives and processes only anonymized data
Response Return
AI response comes back through MCP Server
De-tokenization
Optional: Original values restored for user
Real-World Example
Process payment for John Doe, email john@example.com, card 4532-1111-2222-3333What AI sees
Process payment for PII_PERSON_001, email PII_EMAIL_001, card PII_CREDIT_CARD_001What you get back
Frequently Asked Questions
Why use regex instead of AI for PII detection?
Regex-based detection is deterministic and reproducible. The same input always produces the same output. AI/ML models can be unpredictable and may miss or falsely flag data. For compliance, reproducibility matters.
How accurate is the detection?
Our hybrid approach combines regex patterns with Named Entity Recognition (NER) for high accuracy. All patterns include checksum validation where applicable (credit cards, IBANs, SSNs). False positives are minimized through context-aware scoring.
What happens to my data during processing?
Text is sent to our EU-hosted servers (Hetzner, Germany) over TLS 1.3 for analysis. We don't store your data after processing. With Zero-Knowledge auth, we can't even identify which user made the request.
Can I add custom entity types?
Yes! You can create custom recognizers with your own regex patterns and context words. Custom entities support the same operators (replace, mask, hash, encrypt, redact) as built-in types.
How does reversible encryption work?
The Encrypt operator uses AES-256-GCM encryption with your key. Only you can decrypt. This allows re-identification for audits or legal discovery while keeping data protected in transit and storage.
See It in Action
Try our PII detection and anonymization free with 200 tokens per cycle.
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.