EC2 Instances Purchasing Options
On-Demand Instances
- Usage: Short workloads, unpredictable application behavior
- Pricing: Pay by the second (Linux/Windows after the first minute) or by the hour (other OS)
- Cost: Highest cost, no upfront payments, no long-term commitments
- Flexibility: High, no commitment
Reserved Instances
- Usage: Long workloads (e.g., databases)
- Term: 1 or 3 years
- Discounts: Up to 72% compared to on-demand
- Payment Options: Upfront, Partial Upfront, No Upfront (more upfront payment yields higher discounts)
- Flexibility: Specific instance attributes (type, region, tenancy, OS)
- Scope: Region or a specific Availability Zone (AZ)
- Marketplace: Option to buy/sell reserved instances
Convertible Reserved Instances
- Flexibility: Change instance type, family, OS, scope, tenancy
- Discounts: Up to 66% compared to on-demand
Savings Plans
- Term: 1 or 3 years
- Commitment: Specific amount of usage in dollars