open-cal

What does open-cal do?

• Booking pages. yourdomain.com/<person> lists their event types, and each event has its own picker. Guests see times in their own time zone, 12h or 24h.
• Real availability. Slots come from live Google free/busy across every calendar you tick, including calendars shared from other accounts. Nothing about your calendar is stored or shown, only open start times.
• Google does the invites. The booking is created on the host's calendar with a Meet link. Google sends the invite, the reminders, the reschedule and the cancellation.
• Reschedule and cancel links. Every invite carries a private link where the guest moves or cancels. Moving re-checks free/busy and patches the same Google event.
• A form like Calendly's. Name, email, up to 10 extra guests, plus your own questions. Answers go into the invite and the admin.
• Rules per event type. Length, start-time grid, minimum notice, booking window, buffers, daily caps, extra attendees, extra calendars that must be free, and a calendar colour.
• Follows your calendar. Delete or move a booked meeting in Google Calendar and open-cal follows. A cron job keeps the two in sync.
• Race-safe. A unique index means two guests can never book the same start. The second one is told the time was just taken.
• Admin page. One password, every host on the deploy: pages, event types, hours, calendars and bookings.

What it will not do

• It needs Google Workspace (any paid plan). Personal Gmail calendars work only as extra busy calendars shared with a Workspace host.
• No payments, round-robin, team pooling, Zoom, embeds or SMS. Fork it and add what you need.

Who is it for?

Teams on Google Workspace who pay per seat for a scheduling tool and only need booking pages, real availability and clean invites.

How do you set it up?

You need:

• A Google Workspace account with admin access (for domain-wide delegation).
• A Supabase project (the free tier is enough).
• A Vercel account, or any host that runs Next.js.

1. Create the Supabase project and run the schema.
2. Create a Google Cloud project and a service account with the Calendar API on.
3. Grant the service account domain-wide delegation in Workspace admin.
4. Deploy to Vercel with the environment variables from the README.
5. Point a custom domain at it and add your hosts in /admin.

The full instructions live in the README on GitHub.

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