r8i-flex.4xlarge
Memory optimized · r8i-flex series · Intel Xeon Scalable (Granite Rapids)
- vCPU
- 16
- Memory
- 128 GiB
- Linux / hour
- $1.06
- Per month
- $771
- Per vCPU-hour
- $0.0660
- Per GiB-hour
- $0.00825
Analysis
The r8i-flex.4xlarge is a memory optimized instance in the r8i-flex series with 16 vCPUs and 128 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.4xlarge on AWS Graviton4 costs $0.9426/hour, 11% less ($82.64 a month), though switching means rebuilding software for arm64. The other variants are the r8i.4xlarge at $1.11, the r8gd.4xlarge at $1.18 and the r8a.4xlarge at $1.28.
Running it in N. Virginia instead of São Paulo saves $459 a month per instance: $1.06/hour against $1.68/hour, a 60% spread.
At $1.06/hour on demand in US East (N. Virginia), about $771 a month, the r8i-flex.4xlarge 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 42 current types with 16 vCPUs and similar memory are cheaper. The cheapest of those is the r6g.4xlarge on AWS Graviton2 at $0.8064/hour.
It is size 4 of 7 in the r8i-flex series. Stepping up to the r8i-flex.8xlarge gives 32 vCPUs and 256 GiB for $771 more a month. Dropping to the r8i-flex.2xlarge saves $385 a month.
Price by region (USD per hour)
| Region | Linux | Windows | 1-yr RI | 3-yr RI | |
|---|---|---|---|---|---|
| N. Virginia us-east-1 | $1.06 | $1.75 | – | – | |
| Ohio us-east-2 | $1.06 | $1.75 | – | – | |
| Oregon us-west-2 | $1.06 | $1.75 | – | – | |
| Canada Central ca-central-1 | $1.16 | $1.86 | – | – | |
| São Paulo sa-east-1 | $1.68 | $2.38 | – | – | |
| Ireland eu-west-1 | $1.18 | $1.88 | – | – | |
| London eu-west-2 | $1.24 | $1.94 | – | – | |
| Frankfurt eu-central-1 | $1.27 | $1.97 | – | – | |
| Mumbai ap-south-1 | $1.09 | $1.79 | – | – | |
| Singapore ap-southeast-1 | $1.27 | $1.97 | – | – | |
| Sydney ap-southeast-2 | $1.27 | $1.96 | – | – | |
| Tokyo ap-northeast-1 | $1.27 | $1.97 | – | – |
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.4xlarge |
|---|---|---|---|---|
| r6g.4xlarge AWS Graviton2 Processor | 16 | 128 GiB | $0.8064 | -24% |
| r7g.4xlarge AWS Graviton3 Processor | 16 | 128 GiB | $0.8568 | -19% |
| r5a.4xlarge AMD EPYC 7571 | 16 | 128 GiB | $0.9040 | -14% |
| r6a.4xlarge AMD EPYC 7R13 Processor | 16 | 128 GiB | $0.9072 | -14% |
| r6gd.4xlarge AWS Graviton2 Processor | 16 | 128 GiB | $0.9216 | -13% |
| r8g.4xlarge AWS Graviton4 Processor | 16 | 128 GiB | $0.9426 | -11% |
Cost calculator
Specs
| vCPU | 16 |
|---|---|
| Memory | 128 GiB (8.0 per vCPU) |
| Processor | Intel Xeon Scalable (Granite Rapids) |
| Clock | 3.9 GHz |
| Storage | EBS only |
| Network | Up to 15000 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 |