Cal.diy: booking links without the monthly bill
Open-source scheduling, so clients pick a time themselves instead of ten emails back and forth.
Cal.diy is open-source scheduling software. You share a link, the other person picks a free slot from your calendar, and the meeting is booked. It is the same idea as Calendly, but you can run it yourself.
Why it matters
Booking one call should not take ten emails. A booking link removes the back and forth, and it works the same for a client, a candidate or a friend.
The facts
- Project: calcom/cal.diy on GitHub
- Stars: over 49,000 (as of 7 November 2026)
- Main language: TypeScript
- It is released under the MIT licence.
- Website: https://cal.diy
Before you install it
Self-hosting means you set it up and keep it running. If you only need a link and a calendar, a hosted plan may be less work. The choice is between your time and your money.
I read the project page and its description to write this. I have not audited the code, so treat it as a pointer, not a recommendation to trust it with anything sensitive.