c4.xlarge

Analysis

The c4.xlarge is a compute optimized instance in the c4 series with 4 vCPUs and 7.5 GiB of memory on Intel Xeon E5-2666 v3 (Haswell) (up to 2.9 GHz), which makes it compute-heavy at 1.88 GiB of memory per vCPU.

The newer c5.xlarge on Intel Xeon Platinum 8124M is 15% cheaper at $0.1700/hour, which makes the c4.xlarge hard to justify for new deployments.

It is size 2 of 5 in the c4 series. Stepping up to the c4.2xlarge gives 8 vCPUs and 15 GiB for $145 more a month. Dropping to the c4.large saves $72.27 a month. Unit price is not flat across the series ($0.0442 to $0.0500 per vCPU-hour), so the size changes the rate you pay.

Running it in N. Virginia instead of São Paulo saves $80.30 a month per instance: $0.1990/hour against $0.3090/hour, a 55% spread.

Reserving it for a year with no upfront payment cuts the Linux rate to $0.1260/hour, which beats on demand once it runs more than 63% of the time; three years brings it to $0.0890/hour, 55% below on demand. Windows Server roughly doubles the bill at $0.3830/hour, because the licence is charged per vCPU.

On demand it costs $0.1990/hour in US East (N. Virginia), $145 a month if left running, which puts it mid-table for compute optimized types at the 55th percentile per vCPU ($0.0498 per vCPU-hour) and the 66th percentile per GiB ($0.0265 per GiB-hour).