db.r8a.8xlargevsdb.r8i.8xlarge

db.r8i.8xlarge is 13% cheaper than db.r8a.8xlarge on demand in US East (N. Virginia), saving $460.19 a month. Per vCPU, db.r8i.8xlarge costs 57% less.

At a glance	db.r8a.8xlarge	db.r8i.8xlarge
On-demand	$4.83/hr	$4.20/hr13% less
Lowest rate	$3.864/hr1-yr savings plan, hourly commitment	$3.36/hr13% less1-yr savings plan, hourly commitment
Size	16 vCPUs, 256 GiB	32 vCPUs, 256 GiB

Prices in US East (N. Virginia)

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

Option	db.r8a.8xlarge	db.r8i.8xlarge	db.r8i.8xlarge vs db.r8a.8xlarge
On-demandPay by the hour	$4.83	$4.20	▼ 13%
1-yr reservedNo upfront	—	33% off$2.814	—
3-yr reservedNo upfront	—	53% off$1.974	—
1-yr savings planHourly commitment	20% off$3.864	20% off$3.36	▼ 13%

Key differences

The biggest lead each one has.

Where db.r8a.8xlarge leads

Physical cores32 vs 16

2× higher

Where db.r8i.8xlarge leads

On-demand price$4.20 vs $4.83 per hour

13% cheaper

vCPUs32 vs 16

2× higher

Specs

13 of 23 specs differ. Those are in bold.

Compute7 of 8 differ	db.r8a.8xlarge	db.r8i.8xlarge
vCPUs	16	32
Physical cores	32	16
Threads per core	1	2
Architecture	x86_64	–
Processor	5th Generation AMD EPYC	–
CPU maker	AMD	Intel
Sustained clock	4.5 GHz	3.9 GHz
Burstable	No	No

MemoryAll 1 match	db.r8a.8xlarge	db.r8i.8xlarge
Memory (GiB)	256	256

Networking1 of 3 differ	db.r8a.8xlarge	db.r8i.8xlarge
Network	15000 Mbps	–
Network baseline	15 Gbps	15 Gbps
Network peak	15 Gbps	15 Gbps

Storage1 of 7 differ	db.r8a.8xlarge	db.r8i.8xlarge
Storage	EBS Only	–
EBS baseline bandwidth	10,000 Mbps	10,000 Mbps
EBS max bandwidth	10,000 Mbps	10,000 Mbps
EBS baseline throughput	1,250 MB/s	1,250 MB/s
EBS max throughput	1,250 MB/s	1,250 MB/s
EBS baseline IOPS	40,000	40,000
EBS max IOPS	40,000	40,000

Instance details3 of 3 differ	db.r8a.8xlarge	db.r8i.8xlarge
Family	r8a	r8i
Category	Memory optimized	–
Current generation	Yes	–

Other1 of 1 differ	db.r8a.8xlarge	db.r8i.8xlarge
Hardware Basis	r8a.8xlarge	r8i.8xlarge

On-demand prices by region

Cheapest for db.r8a.8xlarge first. PostgreSQL, USD per hour.

Region	db.r8a.8xlarge	db.r8i.8xlarge	Difference
US East (N. Virginia)Used in summaryus-east-1	$4.83	$4.20	▼ 13%
US East (Ohio)us-east-2	$4.83	$4.20	▼ 13%
US West (Oregon)us-west-2	$4.83	$4.20	▼ 13%
Canada (Central)ca-central-1	$5.216	$4.54	▼ 13%
EU (Ireland)eu-west-1	$5.41	$4.70	▼ 13%
Europe (Spain)eu-south-2	$5.41	$4.70	▼ 13%
Asia Pacific (Tokyo)ap-northeast-1	$5.797	$5.04	▼ 13%
EU (Frankfurt)eu-central-1	$5.893	$5.12	▼ 13%

Keep exploring

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

db.r8a.8xlargeMemory optimized, r8a family

db.r8a.8xlarge prices and specs Every size in the r8a family

Compare db.r8a.8xlarge with

db.r8g.8xlarge db.m8a.8xlarge

db.r8i.8xlarger8i family

db.r8i.8xlarge prices and specs Every size in the r8i family

Compare db.r8i.8xlarge with

db.m8i.8xlarge db.r8g.8xlarge db.r7i.8xlarge db.r7i.8xlarge.tpc2.mem2x db.r7i.8xlarge.tpc2.mem3x

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.

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