Amazon ElastiCache pricing

Amazon ElastiCache is a fully managed caching service that accelerates application speed with microsecond latency. You can also use ElastiCache as a low-latency data store for non-durable data. ElastiCache is compatible with Redis and Memcached to support flexible scaling for demanding, real-time applications. With ElastiCache, you pay only for what you use with no minimum fee. You are charged hourly based on the number of nodes, node type, and pricing model you select.

ElastiCache supports both on-demand nodes, which allow you to pay by hour with no long-term commitments, and reserved nodes, which offer discounts for customers who commit to either one-year or three-year terms. You may also incur costs associated with backup storage, data transfer within or across regions, or use of AWS Outposts.

As part of the AWS Free Tier, you can get started with Amazon ElastiCache for free. Upon signup, new AWS customers receive 750 hours of ElastiCache cache.t2.micro or cache.t3.micro node usage for free for up to 12 months.

The Amazon AWS Free Tier applies to participating services across our global regions. Your free usage under the AWS Free Tier is calculated each month across all regions and automatically applied to your bill – free usage does not accumulate. The AWS Free Tier is not available in the AWS GovCloud (US) regions or the China (Beijing) region at this time.

A node is the smallest building block of an ElastiCache cluster. In general, the current generation types provide more memory and computational power at lower cost when compared to their equivalent previous generation node types. In addition, you will choose a node size. For information on which node size to use, see choosing your node size.

Looking for T1, M1, M2, M3, C1, or R3 Nodes? See the Previous Generation Nodes page.

Using on-demand nodes allows you to pay for memory capacity by hour with no long-term commitments. This model frees you from the costs and complexities of planning, purchasing, and maintaining hardware and helps transform large, fixed costs into smaller variable costs. When using on-demand nodes, you are billed hourly from the time a node is launched until it is terminated. Each partial node-hour consumed will be billed as a full hour.

Reserved nodes provide a significant discount off the ongoing hourly usage rate for the
node(s) you reserve in one-year or three-year terms.
With reserved nodes, you can choose to:

• Pay low hourly charges with no upfront payment
• Make a one-time, partial upfront payment with lower hourly charges
• Pay all upfront for even lower hourly charges

You may designate nodes as reserved nodes by calling the purchasing API or selecting the reserved node option in the AWS console. When purchasing reserved nodes, you must designate a region, node type, payment term, and quantity. The reserved nodes may only be used in the designated region.

Backup storage is the storage associated with the automated and user-initiated snapshots. Amazon ElastiCache provides storage space for one snapshot free of charge for each active ElastiCache for Redis cluster. Additional backup storage is $0.085 per GB per month (same price in all regions). Data transfer for creating and restoring the snapshots is free of charge. Backup storage is only available for ElastiCache for Redis.

AWS Outposts is a fully managed service that extends AWS infrastructure, services, APIs, and tools to customers’ datacenters, co-location spaces, or on-premises facilities. By providing local access to AWS managed infrastructure, AWS Outposts enables you to build and run applications on-premises using the same programming interfaces as in AWS Regions, while using local compute and storage resources for lower latency and local data processing needs. ElastiCache for Outposts only supports M5 and R5 family nodes.

Example 1: Memcached, Single-AZ, On-Demand
You have a simple database caching use case that utilizes Amazon ElastiCache for
Memcached. Your total dataset size is 25 GB, and your application is architected for a single Availability Zone running in U.S. East (N. Virginia). You won’t need to maintain your environment for very long, so you opt for on-demand pricing. You decide to use
cache.m6g.large nodes in a five-node cluster as a balance between network performance, memory capacity, and limiting blast radius of node failures by biasing towards more, smaller nodes in a cluster architecture. As such, the total charges for your workload would be:

On-demand node charges
cache.m6g.large = $0.149 / hour
Total = $0.149 * 5 node cluster = $0.745 / hour

Example 2: High-Read, Multi-AZ, One-year, No Upfront Cost (Caching)
You have a read-heavy workload that utilizes Amazon ElastiCache for Redis. Your total dataset size is 150 GB of 200 byte objects. Your workload is 20 percent writes, 80 percent reads, and approximately 600,000 transactions per second. Since the workload is read-heavy, you use an ElastiCache architecture of one primary node and 5 replica nodes as the replicas can serve the read traffic. You choose the cache.r6g.8xlarge node type as it has enough memory to fit the entire working dataset on each node (keeping in mind the need for reserved memory). You also choose to deploy your workload
across two availability zones in U.S. East (N. Virginia). The overall workload size is predicted to be stable, so you opt to secure one-year reserved instances with no upfront purchase. Additionally, you utilize the free daily backup feature of ElastiCache and take an additional monthly backup. Your total charges are calculated as follows:

Reserved node charges with one-year commitment, no upfront
1 Primary + 5 Replicas = 6 total nodes
cache.r6g.8xlarge 1-year no upfront effective hourly pricing = $2.241 /hour
6 nodes * $2.241 = $13.446 /hour

Data transfer charges
600,000 transactions per second * 200 bytes * 60 minutes/hour * 60 seconds/minute = 432 GB /hour
Approximately 50 percent of your data will cross AZs due to multi-AZ architecture
432 GB * 50% * $0.01 /GB = $2.16 /hour

Backup storage charges
1 snapshot of 150 GB * $0.085 per GB /month= $12.75 /month
$12.75 / 730 hours in month = $0.017 /hour

Total charges
Amazon ElastiCache node charges = $13.446 /hour
Data transfer charges = $2.16 /hour
Backup storage charges = $0.017 /hour
Total = $13.446 + $2.16 + $0.017 = $15.623 / hour

Example 3: High-Write with Global Datastore for Amazon ElastiCache for Redis, Three-year Upfront (Distributed session store use case)
You have a write-heavy distributed session store workload that utilizes Amazon ElastiCache for Redis. Since your users are located all over the United States, you opt to leverage Global Datastore in both U.S. East (N. Virginia) as the primary region and U.S. West (N. California) as the secondary region. Your total dataset size is 25 GB of 200 byte objects, and your traffic pattern is 50,000 writes per second and 50,000 reads per second on the primary region and 50,000 reads on the secondary region. You’ve opted to deploy a clustered architecture across three AZs with three shards and two replica
nodes per shard, in each region. A shard is a collection of one to six Redis nodes. You expect this workload to be very stable and have opted to commit to reserved instances over three years with full upfront purchasing. For backups you are using the included, free backup. Your total charges would be calculated as follows:

Reserved node charges with 3-year commitment, all upfront
3 shards * 3 nodes per shard * 2 regions = 18 total nodes
cache.m6g.xlarge 3-year all upfront effective hourly pricing = $0.134 /hour
18 nodes * $0.134 = $2.412 /hour

Data transfer charges
100,000 reads per second * 200 bytes * 60 minutes /hour * 60 seconds /minute = 72 GB/hour

50,000 writes per second * 200 bytes * 60 minutes /hour * 60 seconds/minute = 36 GB/hour
Approximately 66% of your data will cross AZs due to multi-AZ architecture
(72 GB + 36 GB) * 50% * $0.01/GB = $0.475 + $0.238 = $0.713 /hour

Global Datastore replication traffic OUT = 36 GB /hour
36 GB * $0.02 = $0.72 /hr

Total = $0.72 + $0.713 = $1.433 /hour

Backup storage charge
Included backup per cluster = Free

Total Charges
Amazon ElastiCache node charges = $2.412 /hour
Data transfer charges = $1.433 /hour
Backup storage charges = Free
Total = $2.412 + $1.433 + $0 = $3.845 /hour