An EC2 Capacity Reservation allows you to reserve compute capacity for your EC2 instances in a specific Availability Zone for any duration. This guarantees that AWS will have the capacity available when you need to launch your instances, regardless of overall region demand.

Key Characteristics

1
Guarantee: Ensures capacity availability in a specific AZ for a specific instance type.
2
Usage: Capacity is reserved regardless of whether you have instances running.
3
Billing: You are charged for the reserved capacity whether you use it or not.
4
Flexibility: Can be used in conjunction with Savings Plans and Reserved Instances to optimize costs.