Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

On-Demand Instances

With On-Demand Instances, you pay for compute capacity by the second with no long-term commitments. You have full control over the instance's lifecycle—you decide when to launch, stop, hibernate, start, reboot, or terminate it.

There is no long-term commitment required when you purchase On-Demand Instances. You pay only for the seconds that your On-Demand Instances are in the running state, with a 60-second minimum. The price per second for a running On-Demand Instance is fixed, and is listed on the .

We recommend that you use On-Demand Instances for applications with short-term, irregular workloads that cannot be interrupted.

Work with On-Demand Instances

You can work with On-Demand Instances in the following ways:

If you're new to Amazon EC2, see Get started with Amazon EC2.

On-Demand Instance quotas

There are quotas for the number of running On-Demand Instances per Amazon Web Services account per Region. On-Demand Instance quotas are managed in terms of the number of virtual central processing units (vCPUs) that your running On-Demand Instances are using, regardless of the instance type.

We provide the following quota types for On-Demand Instances:

Quotas apply to running instances only. If your instance is pending, stopping, stopped, or hibernated, it does not count towards your quota.

Each quota type specifies the maximum number of vCPUs for one or more instance families. For information about the different instance families, generations, and sizes, see Amazon EC2 Instance Types.

You can launch any combination of instance types that meet your changing application needs, as long as the number of vCPUs does not exceed your account quota. For example, with a Standard instance quota of 256 vCPUs, you could launch 32 m5.2xlarge instances (32 x 8 vCPUs) or 16 c5.4xlarge instances (16 x 16 vCPUs). For more information, see EC2 On-Demand Instance limits.

Monitor On-Demand Instance quotas and usage

You can view and manage your On-Demand Instance quotas for each Region using the following methods.

To view your current quotas using the Amazon Trusted Advisor console

Open Service limits page in the Amazon Trusted Advisor console.

To configure CloudWatch alarms

With Amazon CloudWatch metrics integration, you can monitor your EC2 usage against your quotas. You can also configure alarms to warn about approaching quotas. For more information, see Service Quotas and Amazon CloudWatch alarms in the Service Quotas User Guide.

Request a quota increase

Even though Amazon EC2 automatically increases your On-Demand Instance quotas based on your usage, you can request a quota increase if necessary. For example, if you intend to launch more instances than your current quota allows, you can request a quota increase by using the Service Quotas console described in Amazon EC2 service quotas.

Query the prices of On-Demand Instances

You can use the Price List Service API or the Amazon Price List API to query the prices of On-Demand Instances. For more information, see Using the Amazon Price List API in the Amazon Billing User Guide.