Open source

Cal.com

Send someone a link, they pick a slot, the invite lands in both calendars, and none of it runs on a domain you are renting.

calcom/cal.diy · ★ 47,409 · last commit 2d ago · AGPL-3.0 · needs 4096 MB RAM · runs on ARM (Pi-friendly)
Cal.com running from the boot-verified compose file
Cal.com, running from the compose file on this page — screenshot from our verified instance, not marketing material.

One tool, 3 subscriptions

The same server can serve several escape hatches — that's how a $5 VPS beats a $50 SaaS bill.

Acuity SchedulingYES
$20/mo · breaks even in 1.9 mo
CalendlyKINDA
$12/mo · breaks even in 15.0 mo
DoodleYES
$10.95/mo · breaks even in 0.6 mo