Amazon EC2 pricing

With Amazon EC2, you pay only for the compute time that you use. Amazon EC2 offers a variety of pricing options for different use cases. For example, if your use case can withstand interruptions, you can save with Spot Instances. You can also save by committing early and locking in a minimum level of use with Reserved Instances.

To learn more Amazon EC2 pricing, choose each of the following five categories.

1️⃣On-Demand Instances　are best for short-term, unpredictable workloads that can't be interrupted. You pay only for the compute time used, with no upfront costs or contracts. They're ideal for development, testing, and applications with irregular usage, but not cost-effective for long-term workloads.

2️⃣Reserved Instances are a billing discount applied to the use of On-Demand Instances in your account. There are two available types of Reserved Instances:

• Standard Reserved Instances
• Convertible Reserved Instances

You can purchase Standard Reserved and Convertible Reserved Instances for a 1-year or 3-year term. You realize greater cost savings with the 3-year option.

Standard Reserved Instances: This option is a good fit if you know the EC2 instance type and size you need for your steady-state applications and in which AWS Region you plan to run them. Reserved Instances require you to state the following qualifications:

• Instance type and size: For example, m5.xlarge
• Platform description (operating system): For example, Microsoft Windows Server or Red Hat Enterprise Linux
• Tenancy: Default tenancy or dedicated tenancy

You have the option to specify an Availability Zone for your EC2 Reserved Instances. If you make this specification, you get EC2 capacity reservation. This ensures that your desired amount of EC2 instances will be available when you need them.

Convertible Reserved Instances: If you need to run your EC2 instances in different Availability Zones or different instance types, then Convertible Reserved Instances might be right for you.
Note: You trade in a deeper discount when you require flexibility to run your EC2 instances.

At the end of a Reserved Instance term, you can continue using the Amazon EC2 instance without interruption. However, you are charged On-Demand rates until you do one of the following:

• Terminate the instance.
• Purchase a new Reserved Instance that matches the instance attributes (instance family and size, Region, platform, and tenancy).

3️⃣EC2 Instance Savings Plans reduce your EC2 instance costs when you make an hourly spend commitment to an instance family and Region for a 1-year or 3-year term. This term commitment results in savings of up to 72 percent compared to On-Demand rates. Any usage up to the commitment is charged at the discounted Savings Plans rate (for example, $10 per hour). Any usage beyond the commitment is charged at regular On-Demand rates.

The EC2 Instance Savings Plans are a good option if you need flexibility in your Amazon EC2 usage over the duration of the commitment term. You have the benefit of saving costs on running any EC2 instance within an EC2 instance family in a chosen Region (for example, M5 usage in N. Virginia) regardless of Availability Zone, instance size, OS, or tenancy. The savings with EC2 Instance Savings Plans are similar to the savings provided by Standard Reserved Instances.

Unlike Reserved Instances, however, you don't need to specify up front what EC2 instance type and size (for example, m5.xlarge), OS, and tenancy to get a discount. Further, you don't need to commit to a certain number of EC2 instances over a 1-year or 3-year term. Additionally, the EC2 Instance Savings Plans don't include an EC2 capacity reservation option.

The key differences between Standard Reserved Instances and Convertible Reserved Instances are:

• Flexibility:

  • Standard Reserved Instances are less flexible. Once purchased, they lock in the instance type, size, region, OS, and tenancy. They are ideal if you know your exact requirements and don't anticipate changes.
  • Convertible Reserved Instances offer more flexibility. You can modify them to change the instance type, size, or region during the term. This flexibility is beneficial if your needs might change over time.

• Discounts:

  • Standard Reserved Instances provide a deeper discount compared to On-Demand pricing, making them more cost-effective for predictable workloads.
  • Convertible Reserved Instances offer a smaller discount in exchange for the flexibility to modify the instance configuration.

• Capacity Reservation:

  • Standard Reserved Instances can be tied to a specific Availability Zone, which provides capacity reservations.
  • Convertible Reserved Instances do not offer the option to reserve capacity in a specific Availability Zone.

In summary, Standard Reserved Instances are best for stable, predictable workloads with known requirements, while Convertible Reserved Instances are better for workloads that require flexibility in instance configuration.

4️⃣Spot Instances offer significant cost savings, up to 90% off On-Demand prices, by using unused EC2 capacity. They're ideal for workloads that are flexible with start and end times or can handle interruptions, like background processing jobs. However, Spot Instances may be delayed or interrupted if capacity becomes unavailable, making them less suitable for tasks that can't tolerate interruptions, such as development and testing.

5️⃣Dedicated Hosts provide physical servers exclusively for your use, allowing you to use existing software licenses and maintain compliance. They are the most expensive EC2 option, available for On-Demand or through reservations.