Amazon EC2 is available for free trial. On-Demand, Savings Plans, Reserved Instances, and Spot Instances are the five payment options for Amazon EC2 instances. You can also pay for Dedicated Hosts, which give you EC2 instance capacity on physical servers that are exclusively yours. Visit the Amazon EC2 Cost and Capacity page for further information on how to save money on Amazon EC2.
You pay for compute capacity by the hour or second, depending on which instances you run, with On-Demand instances. There are no long-term obligations or fees required up front. You can scale up or down your compute capacity based on your application's needs, and you'll only be charged for the instance you utilise.
On-Demand instances should be used for the following scenarios:
Users that favour Amazon EC2's low cost and flexibility over paying up ahead or committing to a long term contract.
Applications with workloads that are sporadic, spiky, or unexpected and can't be interrupted
For the first time on Amazon EC2, applications are being created or tested.