Tool comparison

Kalender Sync vs. CCTSync – local add-in or cloud sync?

CCTSync is one of the most likeable tools in this category: a German Outlook add-in by solo developer Andreas Ulbricht, built privacy-minded, with a free Lite edition – and listed on heise Download. For Windows users on classic Outlook, a solid local tool. Here's an honest look at where CCTSync is strong and where Kalender Sync makes the difference.

Try free for 14 days See the CCTSync view

Background

What can CCTSync do?

CCTSync is an Outlook add-in by German developer Andreas Ulbricht that syncs Google calendars, contacts and birthdays directly with classic Outlook – supporting free Gmail accounts as well as Google business accounts, Outlook 2013 and newer including Microsoft 365 Desktop on Windows. The add-in is deliberately privacy-minded: no CalDAV/CardDAV detour, encrypted exchange only directly with Google, everything else stays local. The Lite edition is free for private users; the full version is a perpetual one-time purchase per user and PC. The current version is 0.1.12.275. The developer communicates transparently: New Outlook is not supported (different technology), while classic Outlook continues until at least 2029 per Microsoft's roadmap.

Strengths

Where CCTSync is strong

A German tool with a transparent developer

CCTSync comes from a German developer with German-language documentation and a direct line – and it's listed on heise Download. The handling of technical limits (New Outlook) is documented with exemplary honesty.

Privacy-minded and local

No third-party server between your calendars: CCTSync exchanges data encrypted directly with Google, everything else stays on your machine. If you don't want another processor in the chain, that's an honest privacy plus.

A free Lite edition for private users

The standard configuration is permanently free for private use – a fair deal for trying it out and for simple setups.

A perpetual one-time purchase instead of a subscription

The full version is a one-time purchase with no time limit – no recurring costs as long as the purchased version keeps running.

Where Kalender Sync wins

A future beyond classic Outlook

CCTSync documents it itself: New Outlook is not supported because it's built on different technology – classic Outlook carries on until around 2029 per Microsoft. That's transparent, but it puts an expiry date on your setup. Kalender Sync works cloud-side directly with the calendar servers: which client you use – New Outlook, classic Outlook, web, Mac, iPhone – doesn't matter to the sync.

Sync runs 24/7 – not only while the PC is on

CCTSync synchronises as long as your Windows machine is running Outlook. PC off, end of day, on holiday? Then the sync stops – and exactly in that window double-bookings happen. Kalender Sync runs on our servers around the clock; your double-booking protection has no gap.

Mac, mobile, device-independent

CCTSync needs a Windows PC with classic Outlook as its sync node – full version licensed per user and PC. You set up Kalender Sync once in the browser (about 2 minutes), and from then on every device benefits automatically: Windows, Mac, iPhone, Android, web.

Genuine live-sharing into other calendars – with two-way sync

CCTSync syncs your own accounts. Kalender Sync not only synchronises bidirectionally between your own calendars, it can also embed your availability into another person's calendar by invitation – as real events, no fragile ICS subscription. They accept once, and from then on everything stays synced automatically.

Three visibility levels per sync – with custom display names

You decide per synchronisation whether only „Busy", „Title + time" or full details are transferred – and you set the name a blocked slot shows up as on the other side. Fine-grained control designed for sharing with third parties – beyond pure self-sync.

More providers than Google ↔ Outlook

CCTSync connects Google with classic Outlook. Kalender Sync connects 9 provider types – Google, Microsoft Outlook/M365, Apple iCloud, GMX, WEB.DE, mailbox.org, Infomaniak kSuite, CalDAV and iCal feeds – and is the only tool in this comparison that connects the German providers GMX & WEB.DE.

A DPA and business support

For companies, law firms and schools, a data processing agreement is part of the Kalender Sync offering – plus a team behind the product rather than one person's availability. Both tools are German and privacy-conscious; for business-critical use, the DPA, contractual framework and support structure count.

Decision guide

When should you pick which?

CCTSync is the right choice if:

You privately just want to sync Google and classic Outlook on one Windows PC – the Lite edition costs nothing.
You deliberately don't want a cloud service between your calendars.
You prefer a German tool with a one-time purchase and plan to stay on classic Outlook.
A Windows machine as the sync node is perfectly sufficient for you.

Kalender Sync is the right choice if:

Your sync should keep running when the PC is off – double-booking protection without a time-window gap.
You use Mac, iPhone, Android or New Outlook – or don't want to rebuild your setup in 2029.
You want to share your availability live into other people's calendars – with three selectable visibility levels.
You need a DPA and a company as your contractual partner for business use.
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 that runs on every device, around the clock?

Connect your calendars in about 2 minutes in the browser – cloud-side, GDPR-compliant and hosted in Germany, with genuine live-sharing and a DPA. The free plan stays free forever.

Try free for 14 days

Currently supported providers

Google Microsoft Apple iCloud KSuite iCal-Feeds

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