The ICS/webcal integration allows you to connect any calendar with Zeeg – regardless of the provider. Through this connection, Zeeg can check your availability and automatically mark booked appointments as unavailable. This helps to avoid double bookings, even when using multiple calendars from different systems.
The ICS/webcal calendar integration is available on all Zeeg plans – including the free Starter plan.
Read-only access
The ICS/webcal integration works only as a read-only connection. Zeeg can check your availability, but cannot create new appointments directly in your connected calendar. Newly booked Zeeg appointments are sent to you via email as an .ics file, which you can manually add to your calendar, or you can configure another calendar (Google, Outlook, Exchange) for automatically adding new appointments.
Which calendars can be connected?
With the ICS/webcal feature, you can connect virtually any calendar that provides a public or private sharing link:
Yahoo Calendar
Fastmail Calendar
Nextcloud Calendar
Thunderbird Lightning
Other calendar services with ICS/webcal export
This integration is particularly useful when your calendar provider doesn't offer a native Zeeg integration.
How the booking process works with ICS/webcal integration
When you share your Zeeg booking link with others, the booking process works as follows:
1. Availability is displayed
The recipient of your link sees your available time slots. Zeeg automatically checks your connected ICS calendar and only shows time slots that are not booked in your calendar.
2. Appointment is booked
The person selects an available time slot, enters their contact details, and completes the booking.
3. Confirmation via email
You receive an email notification with all booking details and an attached .ics file.
4. Manual calendar update required
Since the ICS integration is read-only, you need to manually add the received .ics file to your calendar. Alternatively, you can configure a second calendar (Google, Outlook, Exchange) in your calendar connections to automatically add new appointments.
How to Connect Zeeg with Calendars via ICS/webcal link
1. In your Zeeg dashboard, click on your name in the top left corner and navigate to Calendar Connections in the dropdown menu.
2. If you have already connected a calendar to your Zeeg account, click Add + in the top right corner. If this would be the first calendar you’ll connect with Zeeg, click Add + next to "Connect any calendar via ICS/webcal link"
3. Enter your calendar sharing link (ICS/webcal URL) and optionally a calendar name for better identification.
4. Finally, click Save.
After a successful connection, your calendar will appear in the list of connected calendars and Zeeg will begin synchronizing your availability.
How to find your ICS/webcal sharing link
Each calendar provider offers different ways to generate an ICS/webcal sharing link.
You can find the exact steps for your calendar provider in its support or help center section. Search for terms like "share calendar", "ICS link", "calendar URL", or "subscribe to calendar".
General procedure:
Open the settings of the calendar you want to connect
Look for the "Share" or "Share link" option
Enable sharing and copy the generated link
Tip: Use a private sharing link instead of a public link whenever possible – it's more secure.
Important notes about synchronization
Update interval
Changes in your connected calendar are not immediately visible in Zeeg. Synchronization occurs at regular intervals:
Standard interval: Every 5-15 minutes
For larger calendars: Up to 30 minutes
Plan accordingly for short-notice appointment changes.
What gets synchronized?
✅ Synchronized:
Booked appointments (marked as "busy")
Time periods when you are not available
All-day events
Recurring appointments
❌ Not synchronized:
Appointment details, titles, or descriptions (only availability)
Appointments you create in Zeeg (must be manually added to your calendar)
Participant information
Connect multiple calendars via ICS/webcal
You can connect multiple calendars via ICS/webcal links with Zeeg (e.g., work calendar, personal calendar, project calendar). Simply repeat the steps for each additional calendar.
Zeeg checks all connected calendars and only shows time slots as available that are free in all calendars.
Frequently asked questions (FAQ)
Can Zeeg create appointments in my connected calendar?
No, the ICS/webcal integration is read-only. Zeeg can only check your availability, but cannot create new appointments. You receive booked appointments via email as an .ics file, which you can manually add to your calendar.
Alternatively, you can configure another calendar (Google, Outlook, Exchange) in calendar connections as the target calendar for new appointments.
How long does synchronization take?
Synchronization between your calendar and Zeeg can take 5-30 minutes, depending on the size of your calendar and the number of appointments. For very large calendars (500+ appointments), it may take slightly longer.
Can other people see my appointment details in Zeeg?
No. Zeeg only sees whether a time slot is busy or free. Appointment details, titles, descriptions, or participant information are not transferred or stored.
Can I connect multiple calendars via ICS/webcal?
Yes, you can connect multiple calendars via ICS/webcal links with Zeeg. Create a separate sharing link for each calendar and add it to Zeeg. Zeeg considers all connected calendars when checking availability.
What is the difference between ICS and webcal?
Technically, ICS and webcal are very similar:
ICS (iCalendar): Standard format for calendar data (https://.../*.ics)
webcal: Protocol prefix for calendar subscriptions (webcal://...)
Zeeg supports both formats. Many calendar apps automatically convert webcal:// to https://.
What happens if I disconnect the calendar connection?
If you disconnect the connection, Zeeg can no longer check your availability in that calendar. Appointments already booked in Zeeg remain, but new bookings will no longer consider this calendar when displaying availability.
Does the integration work with free calendar providers?
Yes, the ICS/webcal integration works with all calendar providers that provide an ICS/webcal sharing link – regardless of whether they are free or paid services.
Can I connect a password-protected calendar?
Most ICS/webcal links already contain a unique access key in the URL and don't require an additional password. If your calendar provider requires separate password authentication, the ICS integration may not work. Check your calendar provider's documentation.
How can I improve synchronization speed?
Synchronization speed is determined by Zeeg and your calendar provider. You can:
Use smaller calendars (only share relevant appointments)
Archive old/expired appointments from your calendar
Briefly disconnect and reconnect for urgent changes
For real-time synchronization, we recommend the native integrations with Google Calendar, Outlook, or Exchange.