db.r8a.12xlargevsdb.r8g.12xlarge

db.r8g.12xlarge is 21% cheaper than db.r8a.12xlarge on demand in US East (N. Virginia), saving $1,102.01 a month. They use different processor architectures (x86_64 and arm64), so software built for one may need rebuilding to run on the other.

At a glancedb.r8a.12xlargedb.r8g.12xlarge
On-demand$7.246/hr$5.736/hr21% less
Lowest rate$5.796/hr1-yr savings plan, hourly commitment$4.589/hr21% less1-yr savings plan, hourly commitment
Size48 vCPUs, 384 GiB48 vCPUs, 384 GiB
Processor5th Generation AMD EPYCAWS Graviton4
Architecturex86_64arm64

Prices in US East (N. Virginia)

“Off” is the discount against each type’s own on-demand price. PostgreSQL, USD per hour.

Optiondb.r8a.12xlargedb.r8g.12xlargedb.r8g.12xlarge vs db.r8a.12xlarge
On-demandPay by the hour$7.246$5.736▼ 21%
1-yr reservedNo upfront—33% off$3.843—
3-yr reservedNo upfront—53% off$2.696—
1-yr savings planHourly commitment20% off$5.79620% off$4.589▼ 21%

Key differences

The biggest lead each one has.

Where db.r8a.12xlarge leads
Sustained clock4.5 GHz vs 2.8 GHz
61% higher
Where db.r8g.12xlarge leads
On-demand price$5.736 vs $7.246 per hour
21% cheaper

Specs

8 of 24 specs differ. Those are in bold.

Compute4 of 8 differdb.r8a.12xlargedb.r8g.12xlarge
vCPUs4848
Physical cores4848
Threads per core11
Architecturex86_64arm64
Processor5th Generation AMD EPYCAWS Graviton4
CPU makerAMDAWS
Sustained clock4.5 GHz2.8 GHz
BurstableNoNo
MemoryAll 1 matchdb.r8a.12xlargedb.r8g.12xlarge
Memory (GiB)384384
Networking1 of 3 differdb.r8a.12xlargedb.r8g.12xlarge
Network22500 Mbps22.5 Gigabit
Network baseline22.5 Gbps22.5 Gbps
Network peak22.5 Gbps22.5 Gbps
StorageAll 7 matchdb.r8a.12xlargedb.r8g.12xlarge
StorageEBS OnlyEBS Only
EBS baseline bandwidth15,000 Mbps15,000 Mbps
EBS max bandwidth15,000 Mbps15,000 Mbps
EBS baseline throughput1,875 MB/s1,875 MB/s
EBS max throughput1,875 MB/s1,875 MB/s
EBS baseline IOPS60,00060,000
EBS max IOPS60,00060,000
Instance details2 of 4 differdb.r8a.12xlargedb.r8g.12xlarge
Familyr8ar8g
CategoryMemory optimizedMemory optimized
Current generationYesYes
Normalization factor96192
Other1 of 1 differdb.r8a.12xlargedb.r8g.12xlarge
Hardware Basisr8a.12xlarger8g.12xlarge

On-demand prices by region

Cheapest for db.r8a.12xlarge first. PostgreSQL, USD per hour.

Regiondb.r8a.12xlargedb.r8g.12xlargeDifference
US East (N. Virginia)Used in summaryus-east-1$7.246$5.736▼ 21%
US East (Ohio)us-east-2$7.246$5.736▼ 21%
US West (Oregon)us-west-2$7.246$5.736▼ 21%
Canada (Central)ca-central-1$7.824$6.197▼ 21%
EU (Ireland)eu-west-1$8.114$6.432▼ 21%
Europe (Spain)eu-south-2$8.114$6.432▼ 21%
Asia Pacific (Tokyo)ap-northeast-1$8.695$6.888▼ 21%
EU (Frankfurt)eu-central-1$8.839$6.984▼ 21%

Keep exploring

Each type’s own page, and how it compares with others.

db.r8a.12xlargeMemory optimized, r8a family
db.r8a.12xlarge prices and specsEvery size in the r8a family

Compare db.r8a.12xlarge with

db.r8i.12xlargedb.m8a.12xlarge
db.r8g.12xlargeMemory optimized, r8g family
db.r8g.12xlarge prices and specsEvery size in the r8g family

Compare db.r8g.12xlarge with

db.m8g.12xlargedb.r8gd.12xlargedb.r8i.12xlargedb.r7g.12xlarge

Pay the committed rate, with commitment protection

The best committed rate on these two is 20–53% below on-demand. Connect your cloud accounts to unlock greater savings with commitment protection.

Connect AWS account

AWS RDS PostgreSQL prices in USD. Monthly figures use 730 hours. Prices last updated 12 Nov 2026.