r8i-flex.16xlarge
Memory optimized · r8i-flex series · Intel Xeon Scalable (Granite Rapids)
- vCPU
- 64
- Memory
- 512 GiB
- Linux / hour
- $4.22
- Per month
- $3,083
- Per vCPU-hour
- $0.0660
- Per GiB-hour
- $0.00825
Analysis
The r8i-flex.16xlarge is a memory optimized instance in the r8i-flex series with 64 vCPUs and 512 GiB of memory on Intel Xeon Scalable (Granite Rapids) (up to 3.9 GHz), which makes it memory-heavy at 8 GiB of memory per vCPU.
Within the same generation and size, the r8g.16xlarge on AWS Graviton4 costs $3.77/hour, 11% less ($331 a month), though switching means rebuilding software for arm64. The other variants are the r8i.16xlarge at $4.45, the r8gd.16xlarge at $4.70 and the r8a.16xlarge at $5.11.
Running it in N. Virginia instead of São Paulo saves $1,835 a month per instance: $4.22/hour against $6.74/hour, a 60% spread.
At $4.22/hour on demand in US East (N. Virginia), about $3,083 a month, the r8i-flex.16xlarge is one of the cheaper ways to buy memory optimized capacity: only 24% of the 385 current memory optimized types cost less per vCPU-hour than its $0.0660.
Looking beyond its own line, 10 of 39 current types with 64 vCPUs and similar memory are cheaper. The cheapest of those is the r6g.16xlarge on AWS Graviton2 at $3.23/hour.
It is the largest of the 7 r8i-flex sizes. Dropping to the r8i-flex.12xlarge saves $771 a month.
Windows Server roughly adds 66% to the bill at $7.02/hour, because the licence is charged per vCPU.
Price by region (USD per hour)
| Region | Linux | Windows | 1-yr RI | 3-yr RI | |
|---|---|---|---|---|---|
| N. Virginia us-east-1 | $4.22 | $7.02 | – | – | |
| Ohio us-east-2 | $4.22 | $7.02 | – | – | |
| Oregon us-west-2 | $4.22 | $7.02 | – | – | |
| Canada Central ca-central-1 | $4.63 | $7.42 | – | – | |
| São Paulo sa-east-1 | $6.74 | $9.53 | – | – | |
| Ireland eu-west-1 | $4.73 | $7.52 | – | – | |
| London eu-west-2 | $4.96 | $7.76 | – | – | |
| Frankfurt eu-central-1 | $5.09 | $7.89 | – | – | |
| Mumbai ap-south-1 | $4.36 | $7.15 | – | – | |
| Singapore ap-southeast-1 | $5.09 | $7.89 | – | – | |
| Sydney ap-southeast-2 | $5.06 | $7.86 | – | – | |
| Tokyo ap-northeast-1 | $5.09 | $7.89 | – | – |
Shared tenancy, no pre-installed software. Reserved rates are standard, no upfront, per hour. Prices as of 2026-11-04.
Same shape, other types
| Type | vCPU | Memory | $/hour | vs r8i-flex.16xlarge |
|---|---|---|---|---|
| r6g.16xlarge AWS Graviton2 Processor | 64 | 512 GiB | $3.23 | -24% |
| r7g.16xlarge AWS Graviton3 Processor | 64 | 512 GiB | $3.43 | -19% |
| r5a.16xlarge AMD EPYC 7571 | 64 | 512 GiB | $3.62 | -14% |
| r6a.16xlarge AMD EPYC 7R13 Processor | 64 | 512 GiB | $3.63 | -14% |
| r6gd.16xlarge AWS Graviton2 Processor | 64 | 512 GiB | $3.69 | -13% |
| r8g.16xlarge AWS Graviton4 Processor | 64 | 512 GiB | $3.77 | -11% |
Cost calculator
Specs
| vCPU | 64 |
|---|---|
| Memory | 512 GiB (8.0 per vCPU) |
| Processor | Intel Xeon Scalable (Granite Rapids) |
| Clock | 3.9 GHz |
| Storage | EBS only |
| Network | Up to 30000 Megabit |
r8i-flex sizes
| r8i-flex.large | 2 vCPU | $0.1320 |
| r8i-flex.xlarge | 4 vCPU | $0.2639 |
| r8i-flex.2xlarge | 8 vCPU | $0.5279 |
| r8i-flex.4xlarge | 16 vCPU | $1.06 |
| r8i-flex.8xlarge | 32 vCPU | $2.11 |
| r8i-flex.12xlarge | 48 vCPU | $3.17 |
| r8i-flex.16xlarge | 64 vCPU | $4.22 |