Cal.diy
MIT-licensed scheduling: booking pages, round-robin routing, calendar sync.
Booking system on the client's own domain, embedded in their site.
Every service business needs booking and the licence is MIT, but the README recommends this community edition for personal, non-production use only, and team features were removed. For a paying client, test it hard or use paid Cal.com.
MIT (LICENSE: Copyright (c) 2020-present Cal.com, Inc.); README: '100% MIT-licensed', no Enterprise Edition code.
Legally yes - MIT with no open-core split; but the README warns it is 'strictly recommended for personal, non-production use' and tells commercial users to use Cal.com instead, and Teams, Organizations, Insights, Workflows and SSO/SAML are removed.
RENAMED/SPLIT: Cal.diy is the community edition forked out of Cal.com with all enterprise code removed; contributions here do not flow to Cal.com. Last push 2026-09-26. Self-hosting needs Node, PostgreSQL and your own credentials for calendar/video integrations. cal.diy loads as the self-hosting documentation.
Clinics, consultants, salons, sales teams
Booking system on the client's own domain, embedded in their site.
No hosted Cal.diy ('There is no hosted/managed version'). The parent's commercial product is Cal.com: Free ('Free forever'); Teams $12 per user/month (yearly toggle); Organizations $28 per user/month (yearly toggle); Enterprise Custom.
Calendly (common knowledge; not named in the README). Calendly page today: Free; Standard $10 /seat/mo; Teams $16 /seat/mo; Enterprise starts at $15k /yr (billing toggle state for the $10/$16 figures not confirmed).