Your website can query Google Calendar for real-time availability.
The Process
- Customer selects a date
- Website requests availability
- Backend queries Google Calendar
- Calculate free slots
- Display to customer
Free/Busy API
Google provides a free/busy endpoint that returns busy time ranges.
Your application calculates available slots from this.
Calculating Slots
Given:
- Busy times from Google
- Business hours
- Appointment duration
- Buffer time
Calculate available windows.
Security
Never expose Google credentials in frontend.
All API calls go through your backend.
Caching
Short-term caching can reduce API calls.
Invalidate when bookings occur.
Bookux
Bookux builds availability checking into custom booking interfaces.
Related: Google Calendar API · Real-Time Availability