Tool comparison
Kalender Sync vs. Hetk – which EU sync fits you?
Hetk is a likeable solo project from Estonia: deliberately lean, very affordable and EU-hosted – a foundation we respect. We won't make it easy on ourselves: here's an honest look at where Hetk is strong and where Kalender Sync makes the difference.
Background
What can Hetk do?
Hetk is a calendar sync tool by Hetk Technologies OÜ from Estonia – by its own account deliberately built as a one-person project by developer Andrei Reinus. It synchronises Google Calendar, Microsoft Outlook and Apple iCloud, one-way or two-way per calendar pair. For privacy there are two levers: „Mark as Private" reduces events on the target calendar to a „Busy" block, and title templates allow prefixes like „[Job 1]" in front of the original title. Hosting runs, per its own statements, on Microsoft Azure in the EU (Ireland and the Netherlands), under GDPR and Estonian data protection law. Pricing is aggressive: Personal from $15/year (3 sync pairs), Professional $50/year (8 sync pairs), with a 21-day trial – there is no permanently free plan.
Strengths
Where Hetk is strong
A very low yearly price
$15 per year for 3 sync pairs is a statement – well below almost every competitor. If you only want to sync two or three of your own accounts and price is what matters, you get a lot for very little here.
EU hosting & GDPR – like us
Hetk Technologies OÜ is based in Estonia and hosts, per its own statements, on Azure in the EU. Your data stays under European law – honestly, a US-vs-EU argument doesn't apply here.
Flexible sync directions and title templates
One-way or two-way sync per calendar pair plus templates like „[Job 1] {{original_title}}" – that's well thought out and covers the core self-sync use case cleanly.
A focused indie product with a direct line
One developer, one problem, no feature bloat: Hetk deliberately positions itself as a lean solo project without venture pressure. If you like indie software, you get an honest, focused tool here.
Where Kalender Sync wins
Where Kalender Sync wins
A German company with a DPA, not a foreign OÜ
Kalender Sync is run by PPJ Venture Labs UG (haftungsbeschränkt) in Munich – a German company under German law, with German-language support, and a data processing agreement is part of the offering. Hetk is based in Estonia; no publicly available DPA could be found. For law firms, schools and companies with works-council agreements, having your contractual partner in-country is a real difference.
More providers: GMX, WEB.DE, mailbox.org, kSuite, CalDAV and iCal
Hetk connects Google, Outlook and iCloud. Kalender Sync additionally covers GMX, WEB.DE, mailbox.org, Infomaniak kSuite, generic CalDAV and iCal feeds – and the big German consumer providers GMX and WEB.DE in particular are connected directly by hardly any other sync tool.
Three visibility levels per sync – not just a private toggle
With Hetk it essentially comes down to full details or „Busy" via „Mark as Private". Kalender Sync lets you choose per synchronisation between „Busy only", „Title + time" and full details – and you decide the display name a blocked slot shows up as on the other side.
Genuine live-sharing into other calendars
Hetk syncs exclusively between your own accounts – the tool itself makes clear that nothing is shared with third parties. Kalender Sync can additionally embed your availability into another person's calendar by invitation – no fragile ICS subscription. That sharing flow is a core feature for us.
Reliability beyond a solo project
Hetk says it itself: one person builds and runs the product. That's likeable, but it also means support, development and operations depend on a single human. Kalender Sync is a German product with a team, a public roadmap and users from regulated industries – when your calendar is business-critical, that counts.
A permanently free plan
Hetk has no free plan – after the 21-day trial you pay. With Kalender Sync, one synchronisation is permanently free, with no trial expiry and no credit card. You only pay once you need more connections or providers.
Decision guide
When should you pick which?
Hetk is the right choice if:
- You only want to sync Google, Outlook and iCloud between your own accounts.
- The yearly price is your top criterion – $15/year is hard to beat.
- You deliberately want to support a lean indie tool by a solo developer.
- You don't need sharing into other people's calendars or a DPA.
Kalender Sync is the right choice if:
- You need a German contractual partner with a DPA and German-language support.
- You want to choose per sync between „Busy only", „Title + time" and full details.
- You want to share your availability live into other people's calendars – not just sync your own accounts.
- You want a permanently free plan instead of an expiring trial.
- You want the broadest provider coverage in this comparison: 9 provider types – Google, Microsoft Outlook/M365, Apple iCloud, GMX, WEB.DE, mailbox.org, Infomaniak kSuite, CalDAV and iCal feeds. Kalender Sync is the only tool in this comparison that connects the German providers GMX & WEB.DE.
Ready for calendar sync with a German contractual partner and a DPA?
Connect your calendars in a few clicks – GDPR-compliant, hosted in Germany, with genuine live-sharing.
Try free for 14 daysCurrently supported providers
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