db.r8a.16xlargevsdb.r8i.16xlarge

db.r8i.16xlarge is 13% cheaper than db.r8a.16xlarge on demand in US East (N. Virginia), saving $920.38 a month. Per vCPU, db.r8a.16xlarge costs 42% less.

At a glance	db.r8a.16xlarge	db.r8i.16xlarge
On-demand	$9.661/hr	$8.40/hr13% less
Lowest rate	$7.729/hr1-yr savings plan, hourly commitment	$6.72/hr13% less1-yr savings plan, hourly commitment
Size	64 vCPUs, 512 GiB	32 vCPUs, 512 GiB
Processor	5th Generation AMD EPYC	Intel Xeon Scalable (Granite Rapids)
Architecture	x86_64	x86_64

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.16xlarge	db.r8i.16xlarge	db.r8i.16xlarge vs db.r8a.16xlarge
On-demandPay by the hour	$9.661	$8.40	▼ 13%
1-yr reservedNo upfront	—	33% off$5.628	—
3-yr reservedNo upfront	—	53% off$3.948	—
1-yr savings planHourly commitment	20% off$7.729	20% off$6.72	▼ 13%

Key differences

The biggest lead each one has.

Where db.r8a.16xlarge leads

vCPUs64 vs 32

2× higher

Where db.r8i.16xlarge leads

On-demand price$8.40 vs $9.661 per hour

13% cheaper

Specs

10 of 24 specs differ. Those are in bold.

Compute6 of 8 differ	db.r8a.16xlarge	db.r8i.16xlarge
vCPUs	64	32
Physical cores	64	32
Threads per core	1	2
Architecture	x86_64	x86_64
Processor	5th Generation AMD EPYC	Intel Xeon Scalable (Granite Rapids)
CPU maker	AMD	Intel
Sustained clock	4.5 GHz	3.9 GHz
Burstable	No	No

MemoryAll 1 match	db.r8a.16xlarge	db.r8i.16xlarge
Memory (GiB)	512	512

Networking1 of 3 differ	db.r8a.16xlarge	db.r8i.16xlarge
Network	30000 Mbps	30000 Megabit
Network baseline	30 Gbps	30 Gbps
Network peak	30 Gbps	30 Gbps

StorageAll 7 match	db.r8a.16xlarge	db.r8i.16xlarge
Storage	EBS Only	EBS Only
EBS baseline bandwidth	20,000 Mbps	20,000 Mbps
EBS max bandwidth	20,000 Mbps	20,000 Mbps
EBS baseline throughput	2,500 MB/s	2,500 MB/s
EBS max throughput	2,500 MB/s	2,500 MB/s
EBS baseline IOPS	80,000	80,000
EBS max IOPS	80,000	80,000

Instance details2 of 4 differ	db.r8a.16xlarge	db.r8i.16xlarge
Family	r8a	r8i
Category	Memory optimized	Memory optimized
Current generation	Yes	Yes
Normalization factor	256	–

Other1 of 1 differ	db.r8a.16xlarge	db.r8i.16xlarge
Hardware Basis	r8a.16xlarge	r8i.16xlarge

On-demand prices by region

Cheapest for db.r8a.16xlarge first. PostgreSQL, USD per hour.

Region	db.r8a.16xlarge	db.r8i.16xlarge	Difference
US East (N. Virginia)Used in summaryus-east-1	$9.661	$8.40	▼ 13%
US East (Ohio)us-east-2	$9.661	$8.40	▼ 13%
US West (Oregon)us-west-2	$9.661	$8.40	▼ 13%
Canada (Central)ca-central-1	$10.432	$9.07	▼ 13%
EU (Ireland)eu-west-1	$10.819	$9.41	▼ 13%
Europe (Spain)eu-south-2	$10.819	$9.41	▼ 13%
Asia Pacific (Tokyo)ap-northeast-1	$11.594	$10.08	▼ 13%
EU (Frankfurt)eu-central-1	$11.786	$10.25	▼ 13%

Keep exploring

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

db.r8a.16xlargeMemory optimized, r8a family

db.r8a.16xlarge prices and specs Every size in the r8a family

Compare db.r8a.16xlarge with

db.r8g.16xlarge db.m8a.16xlarge

db.r8i.16xlargeMemory optimized, r8i family

db.r8i.16xlarge prices and specs Every size in the r8i family

Compare db.r8i.16xlarge with

db.m8i.16xlarge db.r8g.16xlarge db.r7i.16xlarge

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.