Acuity Scheduling is an appointment booking platform widely used by salons, clinics, and service businesses, letting customers book a specific time slot instantly online.

Cal.com is an open-source scheduling platform that lets customers book an appointment instantly through a pre-configured booking page, similar in function to Calendly.

Calendly is an elegant and simple scheduling tool for businesses that eliminates email back and forth. It helps save time so that businesses can provide great service and increase sales.

OpenTable is a restaurant reservation platform that lets diners book a table instantly, widely used and trusted across the hospitality industry.

SimplyBook.me is an online booking system used by spas, fitness studios, and service businesses, allowing customers to book a class or appointment in a single tap.