An endpoint is a unique network location that uses an SSL certificate. It is characterized by an IP address and port. For example. bbc.co.uk is a single domain name but it has 8 addresses with port 443 (https://keychest.net/?uuid=f6c6cd90-20c7-11ea-b2ce-551faaa1479e&url=bbc.co.uk).
KEYCHEST limits the number of endpoints you can manage - 500 for free use and 3,000 for ACTIVE, SCALE, and TEAM plans. (subject to change)