Tool comparison
Kalender Sync vs. SyncThemCalendars – which sync fits you?
SyncThemCalendars is quick to set up and has strong reviews – but it's heavily geared toward the Google ecosystem and processes data in the US. Kalender Sync is built on hosting in Germany, a DPA and a permanently free tier. Here's the honest comparison.
Background
What can SyncThemCalendars do?
SyncThemCalendars is a sync tool from Monkey Cube Studio SA (Paris) that is mostly installed as an add-on via the Google Workspace Marketplace and as a Chrome extension. The focus is clearly on Google Calendar, with Microsoft Outlook/Office 365 added; Apple/iCloud support is advertised but is reported by users to be limited. A sync is a single source-to-target connection – two-way syncing is achieved by creating two separate syncs. Per sync, any field (including title and description) can be hidden so that only „Busy" is transferred. Setup is considered fast and reviews are good. According to its privacy policy, however, personal data is stored and processed in the US.
Strengths
Where SyncThemCalendars is strong
Fast setup right inside Google Workspace
As a Marketplace add-on and Chrome extension, SyncThemCalendars is set up in a few clicks – especially convenient if you already work deep in the Google ecosystem.
Granular field-level privacy
You can selectively hide individual fields of copied events – including title and description. That lets you reduce a sync to plain „Busy".
Established with strong reviews
The tool has been on the market for a while and scores consistently high on review portals. If you want a proven solution within the Google world, it's a solid bet.
Where Kalender Sync wins
Where Kalender Sync wins
Hosting in Germany instead of data processing in the US
Per its own privacy policy, SyncThemCalendars stores and processes personal data in the US. Kalender Sync hosts at Hetzner in Nuremberg, as a German company under German law – a clear advantage for GDPR, audits and works-council agreements.
A DPA as standard
A data processing agreement is part of the Kalender Sync offering. No publicly available DPA could be found for SyncThemCalendars – a real issue for regulated industries.
A permanently free plan
SyncThemCalendars has no free tier, only a 14-day trial – after that every plan costs money. With Kalender Sync, one synchronisation is permanently included in the free plan, no credit card required.
Genuine live-sharing into other calendars
SyncThemCalendars copies events between your own connected accounts. Kalender Sync can additionally embed your availability into another person's calendar by invitation, where it stays synced automatically – a dedicated sharing flow, not just mirroring your own accounts.
Fairer sync logic
With SyncThemCalendars, a two-way relationship counts as two syncs – so plan limits are reached faster than they look. With Kalender Sync, a two-way connection is one connection.
Real provider breadth instead of a Google focus
Kalender Sync connects Google, Outlook, Apple iCloud, Infomaniak kSuite and any CalDAV/iCal source on equal footing. SyncThemCalendars is historically Google-centric; Outlook is supported, Apple/iCloud only to a limited extent.
Better value for money
SyncThemCalendars Basic costs $4.99/month for five syncs – of which a two-way relationship already consumes two. Kalender Sync Basic costs €4/month and includes five accounts and five synchronisations, plus a permanently free plan.
Decision guide
When should you pick which?
SyncThemCalendars is the right choice if:
- You work entirely within the Google Workspace ecosystem.
- You want a quickly installed Marketplace add-on.
- US data processing is uncritical for you.
- You don't need a permanently free tier.
Kalender Sync is the right choice if:
- You're based in the EU/DACH and take data protection seriously.
- You need hosting in Germany, a German company and a DPA.
- You also want to connect Apple iCloud, kSuite or iCal feeds on equal footing.
- You want to share your availability live into other calendars – not just mirror your own accounts.
Ready for calendar sync that passes the DACH compliance test?
Connect your calendars in a few clicks – GDPR-compliant, hosted in Germany, with a permanently free plan.
Try free for 14 daysCurrently supported providers
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