Presidio Alternatives

Direct alternatives to Presidio

Presidio is Microsoft's MIT-licensed SDK for finding and anonymizing PII in text, images and structured data, using NER, regex, rules and checksums. Its own README warns that automated detection carries no guarantee of finding everything. Two of the libraries below run Presidio underneath, which means the real choice is often about what wraps it: a wider guardrails layer, a hosted API, or an inference provider that pseudonymizes before the model sees anything.

Guardrails libraries with PII checks built in

• LLM Guard: open-source input and output scanners from Protect AI. Its Anonymize scanner uses Presidio Analyzer and keeps redacted values in a vault; a Deanonymize scanner restores them in the response. Fits when PII is one check among prompt injection, toxicity and secrets.
• Guardrails AI: Python framework that composes validators around LLM calls. Its detect_pii validator on the Guardrails Hub runs on Presidio and can return an anonymized fix. Apache 2.0 core.
• NeMo Guardrails: NVIDIA toolkit with input, dialog, retrieval, execution and output rails defined in Colang. Suited to conversational apps where PII handling sits inside broader flow control.

Hosted instead of self-run

• Lakera: API that inspects inputs and outputs for prompt injection and data leakage, including PII, with a free tier. No detection models to maintain; requests pass through a third party.
• Akumi: EU-hosted OpenAI-compatible inference API with a PII firewall that pseudonymizes data before models see it. Fits when the goal is keeping PII away from the model provider rather than scrubbing text in your own pipeline.