Skip to content
Refine

Glossary · Compute

What is an EC2 Instance Family?

The letter-and-number prefix of an EC2 instance type (m, c, r, t, etc.) that maps to a specific generation, processor, and resource ratio (CPU vs memory).

By HabileLabs

Definition

EC2 Instance Family

An EC2 instance family is the prefix of an instance type like m7i.large — the letter ("m") identifies the family, the number ("7") the generation, the suffix ("i" = Intel) the processor variant. Each family targets a different workload shape:

  • t — burstable, ideal for variable / spiky workloads (web servers, dev environments)
  • m — general purpose, balanced CPU and memory (most default workloads)
  • c — compute optimized, high CPU per dollar (batch, encoding, gaming servers)
  • r — memory optimized (databases, caches, in-memory analytics)
  • i — storage optimized, NVMe SSD attached (high-IO databases, log ingestion)
  • g / p — GPU instances (ML training, inference, graphics)
Why it matters for AWS cost

Matching the workload to the right family is the second axis of right-sizing (after size). A memory-bound workload on a c-family instance pays for CPU it can't use and starves for memory; the same workload on an r-family instance uses the right resource at the right price.

New generations (m7, c7, r7) typically deliver better price-performance than older ones (m5, c5, r5) — the upgrade is usually a cheap savings move when the workload supports the newer CPU.

Find waste like this in your own AWS account free

60-second IAM-role connection. Read-only. No signup needed for the bill analyzer.

Refine is built and supported by HabileLabs, an AWS Advanced Tier Services Partner.

Back to glossary15 terms in the AWS cost & FinOps glossary