Turn Google Calendar into
a booking system
One OAuth click, and every slot your clients see is genuinely free. Real-time availability checks, automatic event creation, and Google Meet links on every booking.
Calendar conflicts cost you clients
is how 'what time works for you?' email threads end
Every back-and-forth message is another chance to lose the meeting. A booking link closes the loop in one step.
calendars is all it takes to start double-booking yourself
Work, personal, a shared team calendar: conflicts live in the gaps between them. Astrocal checks every connected calendar before showing a slot.
is what availability becomes when booking tools sync on a timer
Polling every few minutes leaves a window for conflicts. Astrocal reads your free/busy at the moment of each slot request. There is no cache to go stale.
How Google Calendar works with Astrocal
You: Create event types and connect Google Calendar via OAuth
One OAuth screen, under 30 seconds
Astrocal: Reads FreeBusy data in real time
On every slot request, not cached
Client: Books via your link or widget
Picks from genuinely available slots
Google Calendar: New event created automatically
With invitee details, a Google Meet link, and ICS attachment
Integration capabilities
| Capability | Supported | Notes |
|---|---|---|
| Real-time FreeBusy checks | Yes | Reads availability on every slot request |
| Write booking events to calendar | Yes | Created instantly on booking confirmed |
| Multiple Google Calendars | Yes | Check multiple calendars for conflicts on all plans |
| Two-way sync | Partial | External events block availability in real time. Cancellations in Astrocal remove the Google Calendar event. Cancellations made directly in Google Calendar are not yet synced back. |
| Recurring events | No | On roadmap |
| Google Meet links | Yes | Auto-added to bookings. Zoom and Microsoft Teams supported too |
| Multiple hosts, round-robin | Yes | Each host connects their own calendar |
| Google Workspace accounts | Yes | Personal and Workspace accounts both supported |
| Meeting rooms / resources | No | On roadmap |
Available on all plans including Free.
One OAuth screen. That's the hard part.
Click 'Connect Google Calendar'
You'll be taken to Google's standard OAuth screen. Astrocal requests FreeBusy read access and event write access: the two permissions needed to check availability and create booking events.
Create your first event type
Set a duration, your availability windows, and a buffer between meetings. Astrocal reads your calendar in real time from this point. No additional configuration needed.
Share your booking link or embed the widget
Anyone who books gets a confirmation email. A Google Calendar event is created automatically with the invitee's details.
Pair Google Calendar with Stripe and more
Outlook
Use Microsoft 365? Connect Outlook alongside Google Calendar. Astrocal checks both for conflicts.
Stripe
Require payment at the time of booking. The Google Calendar event is created only after payment clears.
Webhooks
Push booking data to any CRM, Slack, or automation tool via signed webhooks with automatic retries.
Frequently asked questions
Connect Google Calendar in 30 seconds
Real-time sync on every plan. Free to start, no credit card required.