maskwerk / live demo

Test our PII data redaction

maskwerk is the German-first pseudonymisation engine that will power Kontinent's sensitive-data rules. It finds personal data (names, IBANs, tax IDs, cards, addresses), swaps each value for a stable, numbered placeholder, and can turn every one of them back on demand. Paste text or upload a document and watch it work.

Processed in memory on EU infrastructure. Nothing you submit is stored, logged, or used for anything else.

Or start from an example document

Checksums, not guesswork

IBAN (mod-97), Steuer-ID (ISO 7064), SVNR and card numbers (Luhn) are validated mathematically. A real ID is caught; a look-alike is left alone.

Fully reversible

The same value always maps to the same placeholder, and a two-pass reveal restores the original, even when an LLM reshaped the token.

No split-entity leaks

Overlapping detections are resolved before replacement, so a redaction never leaves half a name behind.

Fail-closed

A crashed detector aborts the run instead of quietly redacting less. PDFs are re-scanned after redaction to prove nothing is recoverable.

How it works

Five stages, with a reveal path back. Detection runs multiple readers in parallel (regex and checksums for structured PII, statistical NER for free-text names), then merges their verdicts.

  1. 01/Extract: pull plain text out of TXT, DOCX, XLSX, PDF, or images via OCR.
  2. 02/Detect: regex + checksum validators and NER models scan the text in parallel.
  3. 03/Reclassify: a German gazetteer corrects predictable NER mistakes.
  4. 04/Resolve overlaps: every character is claimed exactly once, with no double or partial masks.
  5. 05/Pseudonymise: spans are replaced back-to-front with stable, reversible placeholders.