Cal.com

Open-source Calendly that you can self-host and actually customize.

Best use cases
Meeting scheduling
Team scheduling
Booking pages
Calendar management
Availability
Pros
Open source
Self-hosting option
No per-seat pricing
Good customization
Active development
Cons
Newer than Calendly
Some features less polished
Self-hosting requires setup
Pricing
freemium
Free self-hosted + paid cloud starting $12/user/mo
Alternatives