t3a.medium

Analysis

The t3a.medium is a general purpose instance in the t3a series with 2 vCPUs and 4 GiB of memory on AMD EPYC 7571 (up to 2.5 GHz), which makes it compute-heavy at 2 GiB of memory per vCPU.

Running it in Mumbai instead of São Paulo saves $26.21 a month per instance: $0.0246/hour against $0.0605/hour, a 146% spread.

At $0.0376/hour on demand in US East (N. Virginia), about $27.45 a month, the t3a.medium is one of the cheaper ways to buy general purpose capacity: only 4% of the 354 current general purpose types cost less per vCPU-hour than its $0.0188.

It is the cheapest of the 2 processor variants AWS sells at this size and generation. The t3.medium on Intel Skylake E5 2686 v5 costs 11% more, and no others also sit above it.

It is size 4 of 7 in the t3a series. Stepping up to the t3a.large gives 2 vCPUs and 8 GiB for $27.45 more a month. Dropping to the t3a.small saves $13.72 a month. Unit price is not flat across the series ($0.00235 to $0.0376 per vCPU-hour), so the size changes the rate you pay.

Reserving it for a year with no upfront payment cuts the Linux rate to $0.0236/hour, which beats on demand once it runs more than 63% of the time; three years brings it to $0.0162/hour, 57% below on demand. Windows Server roughly adds 49% to the bill at $0.0560/hour, because the licence is charged per vCPU.