anonym.plus vs Microsoft Presidio

An open-source Python library you host yourself, versus a packaged, 100% offline desktop app. Your data never leaves your device — there is nothing to breach, no data center, no jurisdiction to trust.

Feature comparison

Competitor data from Microsoft Presidio public documentation, 2026 — verify before relying.

Featureanonym.plusMicrosoft Presidio
Data leaves your device Never — 100% on-device, by default Depends on your deployment — Presidio is a library/service, so most teams run it on a server or cloud VM, meaning documents travel over a network unless you build an air-gapped setup yourself
Deployment Single installable desktop app (Windows/macOS) Python library + Docker images, run as a self-hosted REST service
Offline / air-gap Yes, by default — verified with no internet connection at all Possible, but not packaged — you must provision the environment, pre-fetch NLP models, and manage the container yourself
Entity types 340+ built-in ~20 default recognizers; more require writing custom Python recognizers
Encryption Local AES-256-GCM with an offline key vault An "encrypt" operator exists, but secure key storage is left to the implementer
Account / login required No account for core use — internet is needed only once, for initial license activation No account (open source), but also no vault, UI, or key management — everything is code you write
Pricing model One-time license, no subscription Free (MIT license) — $0 software cost, but the cost shifts to engineering time, hosting, and maintenance
Setup / DevOps None — download, install, run. Built on Presidio + spaCy under the hood Requires Python environment setup, model downloads, and typically Docker/Kubernetes to operate as a service
Compliance angle On-device processing removes the processor/transfer question entirely — an independent penetration test (March 2026) confirmed no document data egress You are the controller and processor of your own deployment; GDPR obligations (Art. 28 agreements, hosting location, breach process) depend entirely on how and where you run it

Microsoft Presidio strengths

  • Backed by Microsoft, actively maintained, with a large open-source community
  • Highly extensible — custom recognizers, custom operators, pluggable NLP engines (spaCy, Stanza, transformer models)
  • Free to use under the MIT license at any scale, no licensing cost
  • Well-documented Python SDK and REST API that drop cleanly into existing data-engineering or MLOps pipelines
  • Includes an image redaction module built on Tesseract OCR

Microsoft Presidio limitations

  • No packaged GUI or desktop app — every user-facing capability has to be built by your own engineering team
  • Requires Python and DevOps expertise to install, configure, and keep running (dependencies, model downloads, containers)
  • Default recognizer set covers a narrower range of entity types out of the box; broader coverage means writing custom recognizers
  • No built-in key vault or local key management — the "encrypt" operator exists, but you own the security of the keys
  • Because most deployments run Presidio as a network service, genuine air-gapped use requires deliberate architecture work that most teams skip in practice

Why choose anonym.plus

  • 100% on-device processing — no document content ever leaves your machine, verifiable by disconnecting the network and running it anyway
  • 340+ PII entity types detected out of the box, no custom recognizer code required
  • Local AES-256-GCM encryption with an offline key vault — keys never touch a server
  • Zero outbound network calls during document processing — an independent penetration test (March 2026) confirmed no document data egress
  • One-time license, no subscription — internet is needed only once, for initial activation
  • Built on Microsoft Presidio + spaCy under the hood, packaged as a ready-to-run desktop app — Presidio's detection engine, without writing Python or standing up infrastructure