Proton Calendar vs Google Calendar: Which Calendar Should You Trust?

Proton Calendar and Google Calendar both keep your schedule, send reminders, and let you invite other people — but they are built for opposite priorities. Proton Calendar encrypts everything end-to-end so that not even Proton can read your schedule. Google Calendar is free, deeply connected to Gmail, Meet, and Tasks, and now uses Gemini AI to find meeting times for you.

The short answer: choose Proton Calendar if your schedule itself is sensitive — medical appointments, legal meetings, private family plans — and you want it encrypted by default. Choose Google Calendar if you live inside Google’s ecosystem, book appointments with clients, or schedule with large teams, because its booking pages, Gmail integration, and AI scheduling have no equivalent in Proton yet. If you already pay for Proton Mail or Proton Unlimited, Proton Calendar costs you nothing extra and is the natural private default; if your contacts all run on Google, switching buys you privacy at the cost of convenience.

How this comparison was put together: every specification below was checked against the companies’ own documentation and pricing pages, including Proton’s plan comparison and calendar support pages and Google’s Workspace appointment-scheduling and Gemini help pages. I also built a test calendar file — a weekly recurring meeting with an attendee — and validated its structure, confirming the standard .ics format both services accept for imports. I could not run signed-in test accounts for screenshots, so where a claim rests on a company’s own statement rather than a live test, the article says so.

Proton Calendar vs Google Calendar at a glance

Which calendar is better for privacy?

Proton Calendar, by a wide margin — and this is the entire reason to switch. Proton encrypts your event titles, descriptions, locations, and attendee lists on your device before they reach its servers, so Proton itself cannot read your schedule. The company is based in Switzerland, where strict privacy law applies, and it funds itself with subscriptions rather than advertising. Google Calendar encrypts data in transit and at rest, but Google holds the keys: your events are readable on Google’s infrastructure and feed the same ecosystem that powers its ad business. Google Calendar shows no ads itself, but that distinction matters less than who can read the data.

The practical trade-off is real, though. Because Proton cannot read your events, it cannot do what Google does with them: it cannot scan your inbox to auto-create events, and it has no AI assistant that reads everyone’s calendars to suggest a meeting time. Privacy here is not a free add-on; it is the product, and the missing conveniences are the price.

How much does each calendar cost?

Both calendars are usable without paying anything, but the free tiers are shaped very differently. Proton’s free plan includes 3 personal calendars with full end-to-end encryption, plus the wider free Proton account. Calendar sharing is the first feature that costs money: Mail Plus at $3.99 per month billed annually ($47.88 per year) adds sharing, 15 GB of storage, and 10 extra email addresses. Proton Unlimited at $9.99 per month billed annually ($119.88 per year) bundles the whole suite — Mail, VPN, Drive, Pass, and Calendar — with 500 GB of storage. Both paid plans carry a 30-day money-back guarantee.

Google Calendar costs nothing with any Google account and shares the account’s 15 GB of pooled storage with Gmail and Drive. There is no paid “Calendar” tier to buy: the extras arrive through Google Workspace, where Business Standard adds multiple booking pages, automated reminders, email verification for bookings, and paid appointment collection through Stripe. If you only need a personal calendar, Google’s free tier is the more generous one; if you need sharing, Proton makes you pay for what Google gives away — because sharing an encrypted calendar is technically harder, and because Proton has no ad revenue to subsidize it.

Can I import my Google Calendar into Proton Calendar?

Yes, and the path is the standard .ics format both services speak. In Google Calendar, Settings, then Import and export, then Export downloads a .zip with one .ics file per calendar. In Proton Calendar, the import tool takes that .ics file and brings in events, dates, times, descriptions, and locations, including recurring series. My test file — a weekly meeting with an attendee, a location, and a description — validated cleanly as a single VEVENT with a weekly recurrence rule, which is exactly the structure both importers expect.

Two limits are worth knowing before you migrate. First, Proton’s free plan caps you at 3 personal calendars, so a Google account with a dozen calendars (family, work, sports teams, holidays) will not fit on the free tier — paid plans raise the ceiling to 20-plus calendars. Second, Proton’s external calendar subscriptions are read-only and capped at 3 on the free plan versus 25 on paid plans, so shared calendars you only view also count against the limit. Migrate the next 60 to 90 days of events first, keep Google read-only for a fortnight, and only then switch your default — the same two-week parallel-run approach that works for any calendar move.

What about booking pages, AI scheduling, and everyday features?

This is where Google Calendar pulls away for work use. Google’s appointment booking pages let clients pick a time from a page you share — one booking page on the free plan, multiple pages with buffer times, booking questions, email verification, and Stripe payment collection on Business Standard. Proton Calendar has no booking-page feature at all: you send invites the old-fashioned way, one event at a time. If you take client bookings, that alone settles the comparison.

Gemini in Google Calendar, available on eligible Workspace plans, scans attendees’ calendars and suggests meeting times that work for everyone, and flags a one-click alternative time when several guests decline. Proton has no AI scheduling and no equivalent of Google Tasks built into the calendar view. On the other hand, Proton covers the everyday basics well: day, week, and month views, reminders, recurring events, time zones, and invitations that work for people without a Proton account. If your calendar life is personal scheduling rather than client wrangling, you will not miss Google’s extras most days.

Which calendar works better with the apps you already use?

Google Calendar wins on breadth. Events auto-appear from Gmail confirmations (flights, hotel bookings, restaurant reservations), Meet links attach to invites in one click, and Tasks live alongside your schedule. It runs on the web, Android, iOS, and Wear OS, with home-screen widgets. Proton Calendar integrates with the Proton suite instead: events can be added from the Proton Mail inbox, and the same account covers encrypted email, cloud storage, a password manager, and a VPN. That suite is the real argument for Proton — the calendar is strongest as one piece of a private stack, in the same way Proton Drive vs Google Drive and Proton Mail vs Tuta showed for storage and email. If you already use Proton Mail, the calendar is a natural, no-cost addition; if you run your life on Gmail, Google Calendar is the path of least resistance.

For scheduling with other people, also consider dedicated tools: our Cal.com vs Calendly comparison covers booking pages in more depth, and Google Sheets vs Excel shows the same ecosystem-versus-privacy pattern in spreadsheets, while Proton Docs vs Google Docs covers the same choice for document editing.

Proton Calendar vs Google Calendar: the verdict by user type

Choose Proton Calendar if: your schedule contains sensitive information and you want it encrypted end-to-end; you already use Proton Mail or Proton Unlimited; you want a calendar funded by subscriptions, not advertising; or you are moving your whole stack off Google and want the calendar to match.

Choose Google Calendar if: you book appointments with clients and need booking pages; you schedule across large teams and want Gemini to find times; you rely on Gmail auto-adding events and Meet links; or your contacts, family, and workplace all run on Google and switching would cost more convenience than it buys privacy.

Use both if: you want the pragmatic middle — keep Google Calendar for shared team and client scheduling, and run a private Proton calendar for personal, medical, and family events. The two coexist fine through .ics exports, and splitting by sensitivity gets you most of Proton’s privacy where it matters without giving up Google’s scheduling power where it pays.

The bottom line: Proton Calendar is the better calendar for privacy, full stop — its encryption model means your schedule is yours alone. Google Calendar is the better calendar for getting things scheduled with other people, thanks to booking pages, Gemini suggested times, and Gmail integration. Pick based on which of those two jobs your calendar actually does most: guarding your time, or coordinating it.

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