Instances›AWS EC2›c8a›c8a.4xlarge
Compute
vCPUs16
Memory32 GiB
Mem / vCPU2.00 GiB
ProcessorEPYC 9R45 Processor
Clock speedUp to 4.5 GHz
Architecturex86_64
Storage
TypeEBS only
Bandwidth10,000 Mbps
Throughput1250 MB/s
IOPS40,000
Networking
PerformanceUp to 15 Gigabit
Max ENIs8
IPv6Yes
GPUNone
Family sizes
c8a.medium1 vCPU · 2 GiB
c8a.large2 vCPU · 4 GiB
c8a.xlarge4 vCPU · 8 GiB
c8a.2xlarge8 vCPU · 16 GiB
c8a.4xlarge16 vCPU · 32 GiB
c8a.8xlarge32 vCPU · 64 GiB
c8a.12xlarge48 vCPU · 96 GiB
c8a.16xlarge64 vCPU · 128 GiB
c8a.24xlarge96 vCPU · 192 GiB
c8a.metal-24xl96 vCPU · 192 GiB
c8a.48xlarge192 vCPU · 384 GiB
c8a.metal-48xl192 vCPU · 384 GiB
c8a.4xlarge

c8a.4xlarge is AWS's compute-optimized EC2 size at 16 vCPU and 32 GiB. In the name, "c" stands for compute, "8" is the generation, "a" marks AMD processors and "4xlarge" is the size within the c8a family. It runs on AMD EPYC 9R45 Processor at Up to 4.5 GHz, and AWS introduced it in December 2025. AWS has since shipped c9g; c9g.4xlarge is the direct replacement at this size. On Rackspace Spot the same shape is ch.vs1.2xlarge — 16 vCPU, 32 GiB, matched on both dimensions, about 95% below the US East (N. Virginia) on-demand rate.

Pricing by region
1 hr
RegionAWS on-demandAWS Spot1-yr Reserved3-yr ReservedRackspace SpotYou save
US East, N. Virginia$0.862$0.292$0.041
$0.821 savings
US Central, Chicagono AWS region$0.011
US Central, Dallasno AWS region$0.111
Hong Kong$0.041
Sydney, Australia$0.041
London, UK$0.131
US West, San Jose$0.002
US Central, Dallas 2no AWS region$0.122
US East, N. Virginia 2$0.862$0.292$0.162
$0.700 savings
When to use it
Good for
  • ●High-traffic web and API serving
  • ●Scientific modelling and simulation
  • ●Ad serving and real-time bidding
  • ●Workloads that fit inside 32 GiB of RAM
  • ●Parallel work that can occupy 16 vCPU
  • ●Network-heavy services — AWS rates this size at Up to 15 Gigabit
Avoid if
  • ●The working set needs more than 32 GiB of RAM
  • ●GPU or FPGA acceleration is needed
  • ●Memory-hungry applications. A memory-optimized family gives more RAM per dollar.
  • ●More than 2.00 GiB of RAM per vCPU is needed — that ratio is fixed for the whole family
  • ●The work is single-threaded. Most of these 16 vCPU would sit idle.
  • ●Local NVMe or instance-store disk is a hard requirement
$629/mo on AWS on-demand against $30/mo on Rackspace Spot for the equivalent — market-priced, not list-priced.
  • Spot sells spare capacity at market prices. It is the cheapest compute on the internet.
  • Prices are set by supply and demand. You pay what the market decides.
  • Compute is delivered as fully managed Kubernetes. All infrastructure is taken care of.
  • Egress costs $0.01/GB after the free allowance. AWS charges $0.09/GB.
Build your Cloudspace
Frequently asked questions