How PIIGhost compares¶
This table is not neutral: the rows are the capabilities PIIGhost was built for, so it naturally comes out ahead. It is here to show what most other tools leave out, not to declare a winner. For a job PIIGhost is not built for, such as releasing a whole dataset, a k-anonymity tool is the right choice.
| Capability | PIIGhost | Presidio | LangChain PII | Cloud (AWS/Azure) | Google DLP | pii-redactor |
|---|---|---|---|---|---|---|
| Detection | regex / NER / LLM | NER + regex + rules + checksum | regex + validators | ML/NER | ML + infoTypes | regex + NER |
| PII handling | reversible token (cache/DB) | mask / token | mask / hash | mask | crypto token (stateless) | reversible token (vault) |
| Transparent restore for the user | ✅ | ⚠️ manual (decrypt) |
❌ | ❌ | ⚠️ re-id via API | ✅ |
| Consistent across a conversation | ✅ per thread | ❌ | ❌ | ❌ | ✅ deterministic | ✅ per session |
| Tool boundary (tool gets the real value, LLM gets the token) | ✅ | ❌ | ✅ | ❌ | ❌ | ❌ |
| Streaming (token-by-token restore) | ✅ | ❌ | ✅ | ❌ | ❌ | ✅ |
| Configurable post-detection stages (linking, fuzzy, expansion, guard) | ✅ | ⚠️ operators only | ❌ | ❌ | ⚠️ transforms | ❌ |
| Unit processed | text / conversation | text | text / conversation | text / documents | text / dataset | text / conversation |
| Self-hosted (OSS) | ✅ | ✅ | ✅ | ❌ cloud | ❌ cloud | ✅ |
| License | MIT | MIT | MIT | Commercial | Commercial | MIT |
Notes: LangChain PII here is the Python PIIMiddleware. The JS piiRedactionMiddleware is the opposite trade-off, reversible but no streaming. Cloud groups AWS Comprehend and Azure AI Language, and Azure's Conversation mode only detects, it does not restore.
Detection-only models (spaCy, GLiNER, Piiranha) and dataset anonymizers (ARX, Amnesia) sit in a different category. The first only find PII, the second transform a whole tabular dataset with k-anonymity or differential privacy, so they are not de-identifying a live conversation.
See Limitations for what PIIGhost does not do and the trade-offs behind these choices.