{
  "slug": "proton-calendar",
  "category": "calendars",
  "name": "Proton Calendar",
  "description": "End-to-end encrypted calendar from Proton for web, Android and iOS. Supports shared calendars, recurring events, time zones, ICS import and subscriptions, and integrates with Proton Mail.",
  "website": "https://proton.me/calendar",
  "source": "https://github.com/ProtonMail/android-calendar",
  "license": "GPL-3.0",
  "platforms": [],
  "jurisdiction": {
    "code": "CH",
    "name": "Switzerland",
    "eyes": null,
    "eu": false,
    "gdpr": true,
    "cloud_act": null
  },
  "pick": false,
  "pick_reason": null,
  "disclosure": null,
  "grade": "C",
  "score": 60,
  "coverage": 100,
  "summary": "Proton Calendar scores 60 out of 100 (grade C) on the calendars criteria. It meets 1 of 4 criteria: no ads or data sales. It partly meets open source, no trackers or telemetry and independent audit. It is based in Switzerland: Not in the Five, Nine or Fourteen Eyes; GDPR-style data protection law.",
  "url": "https://privacyratings.com/calendars/proton-calendar/",
  "markdown": "https://privacyratings.com/calendars/proton-calendar/index.md",
  "answers": {
    "open_source": {
      "title": "Open source",
      "weight": 3,
      "answer": "partial",
      "evidence": "https://github.com/ProtonMail/WebClients/blob/main/LICENSE",
      "note": "The web, Android and iOS apps are GPL-3.0. The server code is not published."
    },
    "no_trackers": {
      "title": "No trackers or telemetry",
      "weight": 3,
      "answer": "partial",
      "evidence": "https://proton.me/support/share-usage-statistics",
      "note": "No third-party trackers, but anonymous usage statistics and crash reports are sent by default and can be turned off."
    },
    "no_ads": {
      "title": "No ads or data sales",
      "weight": 2,
      "answer": "yes",
      "evidence": "https://proton.me/legal/privacy",
      "note": "Funded by paid plans. The privacy policy rules out targeted advertising and profiling."
    },
    "independent_audit": {
      "title": "Independent audit",
      "weight": 2,
      "answer": "partial",
      "evidence": "https://res.cloudinary.com/dbulfrlrz/images/v1707571626/wp-pme/securitum-protonmail-security-audit/securitum-protonmail-security-audit.pdf",
      "note": "Securitum published a full audit of the Proton Mail and Calendar web apps, but it is older than three years."
    },
    "transparency_report": {
      "title": "Transparency report",
      "weight": 2,
      "answer": "n/a",
      "evidence": null,
      "note": "Only applies to hosted services with a website to test."
    },
    "user_notice": {
      "title": "Tells users about requests",
      "weight": 1,
      "answer": "n/a",
      "evidence": null,
      "note": "Only applies to hosted services with a website to test."
    },
    "tls": {
      "title": "TLS configuration",
      "weight": 2,
      "answer": "n/a",
      "evidence": null,
      "note": "Only applies to hosted services with a website to test."
    },
    "security_headers": {
      "title": "Security headers",
      "weight": 1,
      "answer": "n/a",
      "evidence": null,
      "note": "Only applies to hosted services with a website to test."
    },
    "web_standards": {
      "title": "Modern web standards",
      "weight": 1,
      "answer": "n/a",
      "evidence": null,
      "note": "Only applies to hosted services with a website to test."
    }
  },
  "tests": {
    "ssllabs": null,
    "observatory": null,
    "internetnl_web": null,
    "internetnl_mail": null,
    "trackers": [],
    "tested_at": "2026-10-01T07:01:07.067Z"
  },
  "last_modified": "2026-10-01T07:44:20Z"
}