How are Amazon EC2 Instances Priced?
Elastic Compute Cloud (EC2) instances are virtual servers used for running applications in Amazon Web Services (AWS). EC2 instances may be billed on a per-hour or per-second basis:
Per-hour billing means you are billed for at least one hour each time a new instance is started.
Per-second billing means you are billed for at least 60 seconds each time a new instance is started.