⚡Stack Radar

Calendars · Reviewed 26 Oct 2026

Proton Calendar

Privacy-focused calendar with end-to-end encryption for individuals and businesses.

from $3.99 · free tier · proton.me ↗

Paid against free › Calendars › Proton Calendar

Proton Calendar at a glance
74.3MEstimated total trafficModeled monthly visits35.6KRanking keywordsPublic search sample98/100Technical health15 pages checked55.8KReferring domainsLive backlink summary

Overview

01

Summary

The useful answer before the supporting detail.

Proton Calendar is an end-to-end encrypted calendar that combines traditional scheduling features with privacy protections S38. It is used by individuals and businesses who need to keep their schedules confidential, addressing the problem of calendar data being exposed to service providers or third parties S38 S72. Its practical value is that users can manage events, collaborate, and sync across devices while maintaining control over their data S72.

02

Product identity and positioning

Name, category, positioning, audience, and first-party claims.

  • Identity: Proton Calendar is an end-to-end encrypted calendar application from Proton, a privacy-focused company S38 S72.
  • Core purpose: It solves the problem of calendar data being accessible to service providers or third parties by encrypting it S38.
  • Intended users: Individuals and businesses seeking privacy for their scheduling information S38 S72.
  • Product scope: It is a standalone calendar app, part of the broader Proton suite, with web, Android, and iOS apps S72.
  • Positioning: Proton positions it as a calendar that combines expected functionality with robust privacy S38.
  • Claimed distinction: It claims the same end-to-end encryption used in Proton Mail S72.
03

Use cases and audiences

Who the product serves and the jobs it is designed to handle.

AudiencePractical use case
IndividualsManage personal schedules with multiple calendars and reminders while keeping data private S72.
Business usersUse a secure calendar for work, with collaboration features and compliance support S72 S50.
Remote teamsCoordinate across distributed workforces without compromising security S10.
Privacy-conscious professionalsProtect sensitive client projects and meeting details from surveillance S10.

Features

09

Features and capabilities

Core functions and evidence-backed product capabilities.

CapabilityWhat it does
Multiple calendarsCreate separate calendars for different purposes to keep your schedule organized S72.
Event managementCreate events with customizable recurrence (daily, weekly, monthly) and manage invitations from your inbox S72.
Reminders and notificationsSet multiple reminders or email alerts for events S72.
Contact managementUse the Contacts widget to add, remove, merge, or import encrypted contacts S72.
Cross-device syncAccess and edit your calendar on web, Android, and iOS with automatic sync S72.
Import capabilityImport your existing calendar to Proton Calendar S72.
CollaborationShare calendars and collaborate with others, with paid plans required for some features S72.
10

Integrations and ecosystem

Connected products, exports, APIs, and workflow compatibility.

Integration or interfaceTypeWhat it enables
Proton MailIntegrationManage event invitations directly from your Proton Mail inbox S72.
Proton MeetIntegrationGenerate meeting links for calendar invites and integrate with video calls S96 S71.
Contacts widgetIntegrationAdd, remove, merge, or import encrypted contacts within the calendar S72.
Import toolData portabilityImport your existing calendar from other services S72.
ZoomIntegrationGenerate meeting links for video calls in calendar invites S96.

Pricing

11

Pricing and plans

Published plans, free access, trials, credits, and pricing limitations.

Plan or offerVerified price and billingIncludedLimits
Proton Free$0 S57Proton Calendar with a limited number of personal calendars S571 GB storage S57
Mail Plus$3.99 per month billed annually ($47.88 every 12 months) or $4.99 billed monthly S57Proton Calendar with up to 25 personal calendars S5715 GB storage S57
Proton Unlimited$9.99 per month billed annually ($119.88 every 12 months) or $12.99 billed monthly S57All Proton apps, including Calendar S57500 GB storage S57

Competition

12

Competitive landscape

Domains competing for the same organic search demand.

Sampled competitors

CompetitorFirst-page appearancesSampled queriesAverage positionQueries observed
account.proton.me924.4account proton m e, account proton me
account.protonvpn.com114account proton me
reddit.com118account proton me

Website intelligence — Collected evidence

Customers, testimonials, and first-party review claims

No supporting public-page evidence was collected for this category.

Independent review sources discovered

PlatformStatusDiscovered source
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=ch.protonmail.android&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=me.proton.android.drive&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=me.proton.android.lumo&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=proton.android.meet&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=me.proton.android.calendar&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=proton.android.authenticator&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
Googlediscovered_not_scrapedhttps://play.google.com/store/apps/details?id=me.proton.android.wallet&referrer=utm_source%3Dproton.me%26utm_medium%3Dweb%26utm_campaign%3Dpme_all_auto
14

AI visibility

Measured ChatGPT and Google AI mentions with cited sources.

AI-assistant referral traffic

  • Estimated current generative-AI referral share: 0.9%
MonthSource
—All AI assistants
—All AI assistants
—All AI assistants

Website intelligence — Collected evidence

Site-stated AI capabilities

Page typeEvidenceSource
pricingExplore and create with AI while staying in control of your information. Start with Free or upgrade to Plus for advanced features and unlimited chats.https://proton.me/lumo/pricing
pricingUse Lumo AI Plushttps://proton.me/lumo/pricing

These are first-party product claims, not independent measurements of AI-search visibility.

15

Marketing opportunities

Actions calculated directly from the collected evidence.

OpportunityRecommended actionEvidence
Competitor gapReview the sampled queries where account.proton.me appears.9 first-page appearances across account proton m e, account proton me

Website intelligence — Collected evidence

Website evidence gaps

  • integrations: no usable public page was collected; verify whether the site publishes this evidence.
  • customers: no usable public page was collected; verify whether the site publishes this evidence.
  • reviews: no usable public page was collected; verify whether the site publishes this evidence.
  • changes: no usable public page was collected; verify whether the site publishes this evidence.
  • identity: no usable public page was collected; verify whether the site publishes this evidence.
  • technical: no usable public page was collected; verify whether the site publishes this evidence.

Trust and proof

16

Customers, proof, and reviews

Published proof, customer signals, and review evidence.

Independent reviews

PlatformPageHow it was foundNote
TrustpilotProton Reviews 185Grounded web search# Proton Reviews 185 • 2.7 Write a review Visit website ... be a huge task. Completely irresponsible to offer ... 2.7 #### Poor 185 reviews 5-star 4-star 3-star 2-star 1-star Replied to 97% of negative reviews Typically replies within 48 hours
TrustpilotProton Mail Reviews 1,621Grounded web search# Proton Mail Reviews 1,621 ... 2.4 ... Most reviewers were unhappy with their experience overall. Many people expressed significant dissatisfaction with the customer service, citing unhelpful responses, slow communication, and an inability to resolve critical issues. Users frequently reported being locked out of their accounts, having ac counts disabled for unclear reasons, and struggling to regain access to important data. The inflexibility of subscription plans and issues with account managem
ScamRavenIs proton.me scam or legitimate? - ScamRaven / Legit VerdictGrounded web searchIs proton.me a scam? No. Based on site facts, long ... , proton.me is legitimate. Public reviews are largely positive about security and privacy. Some users report slower support ... are common trade-offs with strong encryption and a large product suite.
TrustpilotProton Mail Reviews 1,000Grounded web search# Proton Mail Reviews 1,000 • 2.1 Software Company Write a review Visit website Write a review ... #### Poor 1K reviews 5-star 4-star 3-star 2-star 1-star Replied to 97% of negative reviews Typically replies within 24 hours

Customer proof

No named customers, testimonials, or customer case studies were found.

Independent mentions

  • Ask HN: Have you migrated to Proton mail/calendar/pass/etc.? How was it? — martijnarts on April 22, 2024 / next – I used ProtonMail for a few years, but ended up switching to FastMail. Too much became too difficult due to the full E2EE, especially the calendar app was impossible to use together with other apps or even other people. The email app was fine, but not great, and again E2EE was difficult to use with other apps. Especially on desktop I like using a dedicated app, and their bridge just never cut it for me in terms of stability. The VPN worked well! I ended
  • Proton Meet / Hacker News — Proton Meet / Hacker News Proton Meet (proton.me) 152 points by Einenlum 5 months ago / hide / past / favorite / 60 comments ... I wish Proton would focus on all of the missing features within their existing product suite before creating even more
  • Proton and Standard Notes are joining forces / Hacker News — without updates. Email is great, I'd still highly recommend it. But I wish they would restrict their WIP and focus on fewer things ... and the iOS app is extremely good too. It's also very clear to me that the Proton team work extremely hard, and listen
  • Reminder that Proton is not "private". They have all the keys, and willingly ope... — not "private". They have all the keys, and willingly operate in a jurisdiction where they bend over backwards for ridiculous court orders. From their own transparency page: Number of legal orders: 6,378 Contested orders: 407 Orders complied with:

External links were grounded in one live web search. Search snippets are leads, not independently scraped page content; rejected links remain available in Review evidence.

17

Company, security, and trust

Ownership, policies, security signals, and public trust evidence.

SignalFindingSource
Company and ownershipProton is incorporated and headquartered in Switzerland. This means all user data is protected by strict Swiss privacy laws and Swiss neutrality.source
Contact and supportNot published on the collected pages.—
Legal and privacySimplify compliance with industry regulations like HIPAA, GDPR, and GLBA while building client and stakeholder trust. Docs’ end-to-end encryption helps you handle sensitive data while minimizing the risk of exposure.source
Security and complianceChoose the world’s largest encrypted calendar servicesource
Uptime and status pageNot published on the collected pages.—
Domain registered2010-10-10—
Domain expires2028-10-10—

Not found on the collected pages: contact and support, uptime and status page. This only means Scout did not find it on the pages it read; it says nothing about the company itself.

18

Documentation and product updates

Help resources, product guidance, and visible changes over time.

Resource or updateTypeWhat is availableDate or freshness
Create and collaborate with secure online documents / ProtonDocumentationCollaborate in real-time, share documents safely, work from any device, and keep your data yours with Proton Docs. (source)Not dated
Contact and supportSupportPublic contact and support channel. (source)Not dated
Proton Calendar / ProtonRoadmapPublic product roadmap. (source)Not dated

Not found in the collected public sources: changelog or release notes, status page, separate help center or knowledge base.

Technical

19

Technical and delivery signals

Delivery model, platforms, API, data ownership, reliability claims and release activity.

SignalFindingSource
Delivery model (cloud, self-hosted, desktop, browser extension)Proton Calendar is available as a web app and mobile apps for Android and iOS S72.S72
Platforms and appsApps are available for web, Android, and iOS S72.S72
API and extensibility (API, SDK, webhooks, MCP, plugins)Not published on the collected pages.—
Data ownership and exportUsers can import calendars, but export options are not specified S72.S72
Performance and reliability claimsNot published on the collected pages.—
Release activityNot published on the collected pages.—
20

Measured infrastructure

Domain, certificate, and hosting signals, measured directly.

SignalFinding
TLS certificateLet's Encrypt, valid, expires 2026-12-01
Security headersHSTS, CSP, X-Content-Type-Options, Referrer-Policy
Headers not servedX-Frame-Options
Mail handled bymail.protonmail.ch, mailsec.protonmail.ch
Nameserversns2.proton.me, ns3.proton.me

Not measurable: wayback: rate limited by archive.org, ladder stopped after 1 probe(s). A gap here means the lookup was unavailable, not that the finding is negative.

21

Technical site audit

A bounded multi-page crawl with page-level issues and URLs.

Scout — Bounded technical crawl

  • Pages crawled: 15 of 15 maximum
  • Technical health: 98/100
  • Critical issues: 0
  • Warnings: 6
  • Notices: 1

Issues

SeverityIssueValueAffected URL
warningMissing canonical URL—https://proton.me/business
noticePage is marked noindex—https://proton.me/business
warningTitle length should be reviewed74https://proton.me/mail
warningTitle length should be reviewed68https://proton.me/pass
warningTitle length should be reviewed69https://proton.me/meet
warningTitle length should be reviewed68https://proton.me/drive/sheets
warningTitle length should be reviewed85https://proton.me/business/vpn

Crawled pages

StatusTitleH1sWordsResponseURL
200Proton: Privacy by default12017732 mshttps://proton.me/
200Secure business solutions \Proton for Business12142292 ms
200Proton Pricing Plans - Free & Paid Plans \Proton11935858 ms
200Proton Mail: Get a free email account with privacy and encryption \Proton11988876 ms
200Proton Drive: Free secure cloud storage \Proton11929797 ms
200Proton Pass: Free password manager with identity protection \Proton12109268 ms
200About Lumo, the privacy-first AI assistant \Proton11789250 ms
200Proton Meet: Secure, end-to-end encrypted video conferencing \Proton11290230 ms
200Proton Calendar: Your schedule is worth protecting \Proton1870204 ms
200Create and collaborate with secure online documents \Proton11079223 ms
200Protect and analyze data with encrypted online spreadsheets \Proton1956211 ms
200Proton Authenticator: Private, secure 2FA authenticator \Proton11713241 ms
200Proton Wallet: A secure, self-custodial Bitcoin wallet \Proton11088230 ms
200Secure business email and calendar app \Proton for Business11831240 ms
200Secure business VPN for small, medium, and enterprise companies \Proton for Business11348219 ms

This is a bounded Scout crawl. Core Web Vitals and Lighthouse scores are not claimed unless a dedicated performance audit is connected.

22

Search Console and Analytics

First-party search and behavioral data connection state.

Modeled acquisition channels

ChannelEstimated share
direct63.6%
search12.2%
search organic11.6%
search paid0.6%
social7.0%
social organic6.8%
social paid0.2%
referrals2.6%
paid referrals0.6%
mail12.7%
gen ai0.9%
affiliate0.3%
other0.0%

First-party connections

IntegrationStatusData available after connection
Google Search ConsoleNot connectedClicks, impressions, CTR, average position, queries, pages, countries, and devices
Google AnalyticsNot connectedOrganic sessions, engagement, landing pages, conversions, geography, and devices

No first-party Search Console or Analytics numbers are shown until the site owner authorizes the corresponding Google account. Scout traffic model values above are modeled estimates, not private analytics totals.

Limits and method

23

Limitations and open questions

Known constraints and missing evidence from the collected pages.

The collected pages do not mention specific competitors or alternative products. Evidence gaps include lack of detailed pricing for business plans, absence of API documentation, and no explicit data export features. Open questions remain about the exact number of calendars on free plans (FAQ says 1, table says 3) and the availability of a desktop app.

24

Sources, method, and limitations

Evidence inventory, collection method, provider use, and constraints.

This report is based on 15 collected pages from proton.me, including product pages, pricing pages, and feature lists. The evidence catalog includes 180 items, with sources ranging from identity and pricing to features and trust. External proof search was used but did not verify any customer reviews or ratings. Limitations include potential outdated information and lack of independent verification of claims.

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