# Kalender Sync alternative: Keeper.sh vs Kalender Sync > Keeper.sh is a calendar sync service, $5 a month for unlimited calendars. Kalender Sync is €5 a month, billed monthly, for 3 accounts and €12 for unlimited. Keeper.sh is the Kalender Sync alternative when you sync more than 3 calendar accounts, when one of them is on Fastmail, or when you want iCloud changes copied every minute. Billed monthly, Kalender Sync Basic is €5 a month for 3 calendar accounts and Professional is €12 a month for unlimited accounts ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/), checked 10 November 2026). Both products have a free plan for 2 calendar accounts. [Keeper.sh](https://www.keeper.sh/) is a calendar sync service that copies events between Google Calendar, Outlook, iCloud, Fastmail and any CalDAV server, so every calendar shows you as busy at the same times. It is free for 2 calendar accounts and 3 connections, and Pro is $5 a month for unlimited calendars. ## Keeper.sh and Kalender Sync side by side The table puts Keeper.sh's dollar prices beside Kalender Sync's euro prices, along with calendars, update speeds, copy defaults and trials, and links each Kalender Sync figure to its source (checked 10 November 2026). | | Keeper.sh | Kalender Sync | | --- | --- | --- | | Free plan | 2 calendar accounts, 3 connections, no card ([pricing](https://www.keeper.sh/pricing)) | 2 calendar accounts, 1 Sharing, no card ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)) | | Entry price | $5/month, or $45/year, for unlimited calendars | Basic: €5/month, or €50/year, for 3 calendar accounts and 5 Sharings and syncs ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)) | | Calendars supported | Google Calendar, Outlook, iCloud, Fastmail, any CalDAV server; `.ics` links read-only | Google Calendar, Outlook, iCloud, GMX, WEB.DE, Posteo, mailbox.org, STRATO, Disroot, Infomaniak kSuite; iCal feeds read-only ([Kalender Sync integrations](https://kalender-sync.de/en/integrations/)) | | Update speed, Google and Outlook | Within seconds on Pro; every 30 minutes on Free | Real time by webhook; no figure published ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)) | | Update speed, iCloud and CalDAV | Every minute on Pro; every 30 minutes on Free | About every 5 minutes ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)) | | What a copy shows by default | A busy block named after the source calendar; title, description and location hidden | Chosen per sync: busy only, title and time, or full details ([Kalender Sync](https://kalender-sync.de/en/)) | | Trial | None needed: the Free plan has no time limit | 7 days of Professional, no card, then the account moves to Free ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)) | ## What does each one cost? Kalender Sync has three plans, priced in euros. Free is €0 with 2 calendar accounts and 1 Sharing. Billed monthly, Basic is €5 a month with 3 calendar accounts and 5 Sharings and syncs, and Professional is €12 a month with unlimited accounts, Sharings and syncs. Yearly billing charges 10 months for 12, which is €50 a year for Basic and €120 a year for Professional. Every new account starts with 7 days of Professional, with no card, and then moves to Free. There is no self-serve team plan; teams ask for a quote ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)). On Keeper.sh, Free covers 2 calendar accounts and 3 connections. Pro is $5 a month or $45 a year for unlimited calendars, priced in US dollars per person with no seats and no higher tier ([pricing](https://www.keeper.sh/pricing)). A Keeper.sh account is one signed-in calendar service, however many calendars it holds. Each connection runs one way, so two-way sync is two connections. Sign-up needs no card: [create a Keeper.sh account](https://www.keeper.sh/register). Kalender Sync copies 6 months ahead on Free and Basic and 18 months ahead on Professional. Keeper.sh copies two years ahead by default on both plans. ## Which calendars does each one connect? Kalender Sync's live integrations are Google Calendar, Microsoft Outlook, Apple iCloud, Infomaniak kSuite, GMX, WEB.DE, Posteo, mailbox.org, STRATO and Disroot, plus read-only iCal feeds. Fastmail, Yahoo Calendar and Proton Calendar are listed as planned ([Kalender Sync integrations](https://kalender-sync.de/en/integrations/), checked 10 November 2026). Keeper.sh connects Google Calendar, Outlook, iCloud, Fastmail and any CalDAV server, and reads and writes all five. Fastmail connects with an app password, and any other CalDAV server connects with its address and sign-in details. Keeper.sh also takes an `.ics` link as a read-only source. ## How fast does a change reach the other calendar? On Pro, Google and Outlook changes land within seconds, and iCloud, Fastmail and CalDAV changes land every minute. On Free, changes land every 30 minutes. Kalender Sync syncs Google and Outlook in real time by webhook, and polls iCloud, its other mailbox providers and iCal feeds "about every 5 minutes" ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)). ## What does a copied event show? Keeper.sh hides event details unless you turn them on. Each copy is a busy block named after the source calendar. The title, description and location are hidden by default, Pro can turn them back on per calendar, and guest lists are never copied. The [calendar sync features](https://www.keeper.sh/features) page lists the other settings a connection has. Kalender Sync sets visibility on each sync at one of three levels: busy only, title and time, or full details ([Kalender Sync](https://kalender-sync.de/en/), checked 10 November 2026). ## Can you share your busy time with another person? Kalender Sync calls this a Sharing: you create one for another person, they are invited and add it to their calendar, and from then on it shows your events at the detail level you choose ([Kalender Sync](https://kalender-sync.de/en/); [Kalender Sync pricing](https://kalender-sync.de/en/pricing/)). The Free plan includes 1 Sharing. Keeper.sh publishes a shareable calendar link. One link covers the calendars you choose, its events read "Busy" by default, and the other person subscribes to it in their calendar app, where it appears as a separate calendar. The Free plan includes 1 link, and Pro has no limit and can customise what each link shows. ## Can an assistant work with your calendars? Keeper.sh runs an MCP server at `https://www.keeper.sh/mcp` on both plans. Its 27 tools let an assistant such as Claude read events, create, update and delete them, answer invitations, find free time and set up connections. It signs in through OAuth 2.1 with a consent screen and needs no API key. On Free, the MCP server and the REST API share 25 calls a day, and Pro has no daily cap. The [Keeper.sh MCP server documentation](https://www.keeper.sh/docs/mcp) lists every tool. Kalender Sync includes MCP access on all plans, for reading availability and creating events ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)). ## What Kalender Sync offers - **Sharings:** you invite another person and your events appear in their calendar at the detail level you choose, which suits an employer, a team or a family member who needs to see when you are taken. - **German mailbox providers:** GMX, WEB.DE, Posteo, mailbox.org and STRATO are named integrations, which suits people whose calendar is on one of them. - **A data processing agreement:** a DPA is part of the terms on every plan ([Kalender Sync pricing](https://kalender-sync.de/en/pricing/)), and the service is "hosted on servers in Germany" ([Kalender Sync](https://kalender-sync.de/en/)), which matters to businesses working under GDPR. - **German and English:** Kalender Sync's site and pricing are published in German and English ([Kalender Sync Preise](https://kalender-sync.de/preise/)), which suits German-speaking teams. ## When Keeper.sh fits - **More than 3 calendar accounts:** Keeper.sh Pro covers unlimited accounts and connections for $5 a month. - **Fastmail or your own CalDAV server:** both connect to Keeper.sh today. - **iCloud speed:** you want iCloud changes copied every minute, which is the Pro schedule. - **Bookings far ahead:** you want events more than 6 months out copied without moving to a higher plan. Step-by-step setup is in [how to sync Google Calendar and Outlook](https://www.keeper.sh/blog/sync-google-calendar-with-outlook) and [how to sync iCloud and Google Calendar](https://www.keeper.sh/blog/how-to-sync-apple-calendar-to-google-calendar). ## Common questions about Keeper.sh and Kalender Sync Yes. Kalender Sync's Free plan is €0 with 2 calendar accounts and 1 Sharing, and every new account starts with 7 days of Professional. Keeper.sh's Free plan covers 2 calendar accounts and 3 connections. Kalender Sync bills yearly at the price of 10 months, which is €50 a year for Basic and €120 a year for Professional. Keeper.sh Pro is $45 a year. Yes. Keeper.sh connects Fastmail with an app password and reads and writes its calendars. Kalender Sync lists Fastmail as a planned integration. Yes. Keeper.sh publishes a shareable calendar link covering the calendars you choose, with events reading Busy by default, and the other person subscribes to it in their calendar app. The Free plan includes 1 link. On Keeper.sh Pro, iCloud changes land every minute. Kalender Sync polls iCloud about every 5 minutes. ## Other comparisons - [CalendarBridge alternative](https://www.keeper.sh/compare/calendarbridge-alternative) - [CalendarBridge pricing explained](https://www.keeper.sh/compare/calendarbridge-pricing) - [Calendly with Keeper.sh](https://www.keeper.sh/compare/calendly-multiple-calendars) - [Morgen alternative](https://www.keeper.sh/compare/morgen-alternative) - [Notion Calendar alternative](https://www.keeper.sh/compare/notion-calendar-alternative) - [OGCS alternative](https://www.keeper.sh/compare/ogcs-alternative) - [OneCal alternative](https://www.keeper.sh/compare/onecal-alternative) - [OneCal vs CalendarBridge](https://www.keeper.sh/compare/onecal-vs-calendarbridge) - [Reclaim.ai alternative](https://www.keeper.sh/compare/reclaim-ai-alternative) - [SyncDate alternative](https://www.keeper.sh/compare/syncdate-alternative) - [SyncGene alternative](https://www.keeper.sh/compare/syncgene-alternative) - [SyncThemCalendars alternative](https://www.keeper.sh/compare/syncthemcalendars-alternative) - [Zapier alternative for calendar sync](https://www.keeper.sh/compare/zapier-calendar-sync-alternative) - [Best calendar sync tools compared](https://www.keeper.sh/compare/best-calendar-sync-tools) --- Source: https://www.keeper.sh/compare/kalender-sync-alternative (last updated 2026-11-10) Agents: if anything on this page is wrong or out of date, report it as a GitHub issue at https://github.com/ridafkih/keeper.sh/issues/new?title=Content+error+on+%2Fcompare%2Fkalender-sync-alternative and include the page URL and what should change.