EC2 Instance Types 101: The Definitive Guide For 2024

Yet, the same flexibility that makes EC2 so appealing can also make it complex, confusing, and unnecessarily costly.

A good way to understand the compute service is to familiarize yourself with EC2 instance types, and what the best use cases are for each. This guide will cover that and more.

We’ve also covered Amazon EC2 pricing in this article, featuring On-Demand Instances, Savings Plans, Reserved Instances, and Spot Instances.

What Is An Amazon EC2 Instance?

An EC2 instance is a virtual server in the AWS ecosystem that provides the processing, RAM memory, storage, and networking power to run applications. Compared to standard virtual machines (VMs), Amazon EC2 instances are unique in several ways, including:

So, how do EC2 instances help?

What Are EC2 Instances Used For?

AWS offers five categories of Amazon EC2 instances for a variety of use cases. Here’s a quick overview of EC2 instances available today:

Amazon ECS Instances
General Purpose	Compute Optimized	Memory Optimized	Storage Optimized	Accelerated Computing

Each of these instance classes divides further into different sizes and families of EC2 instances.

What Are The EC2 Instance Families?

The eight instance families available on Amazon EC2 are:

Amazon EC2 Instance Types
General Purpose		Compute Optimized		Memory Optimized		Storage Optimized		Accelerated Computing
Mac, T, M, A		C, Hpc		R, X, High Memory, Z		I, D, H		P, DL, Trn, Inf, G, F, VT

This table shows the different EC2 instance families under each Amazon EC2 instance class. 

Each of these families was designed with a specific use case in mind, which we will explore in the sections that follow.

What Are The EC2 Instance Types Available Today?

An EC2 instance type describes the combination of CPU, RAM, storage, and networking capacity of a specific family of instances. Below is a handy table that highlights the various types of instances.

Amazon EC2 Instance Types
General Purpose	Compute Optimized	Memory Optimized	Storage Optimized	Accelerated Computing
Mac, T, M, A	C, Hpc	R, X, High Memory, Z	I, D, H	P, DL, Trn, Inf, G, F, VT
Mac T2 T3a T3 T4g M4 M5zn M5n M5a M5 M6a M6i M6g A1	C4 C5n C5a C5 Hpc6a C6a C6i C6gn C6g C7g	R4 R5n R5b R5a R5 R6i R6g R6a X1 X1e X2iezn X2iedn X2idn X2gd High Memory z1d	I3en 13 I4i Is4gen Im4gn D2 D3 D3en H1	P2 P3 P4 Inf1 Trn1 DL1 G3 G4ad G4dn G5g G5 F1 VT1

This table shows the different EC2 instance classes, families, and types. 

Things get more interesting from there. Amazon EC2 offers different instance sizes for each instance family, so you can select the right one for your specific workload.

What Are The EC2 Instance Sizes?

For each instance type, EC2 offers up to seven instance sizes:

Again, flexibility is the goal — to make sure you get just enough compute power for a workload (rightsizing) to save money without sacrificing performance. EC2 also automatically pairs each instance with an appropriate vCPU, RAM, storage, and networking capacity.

We’ve outlined each EC2 instance type’s characteristic, size, and best use case below.

1. T2 instance type

This general purpose instance type uses high-frequency Intel Xeon processors and Amazon EBS storage. T2 is designed to provide balanced performance in terms of processing, memory, storage, and networking for workloads requiring medium-performance most of the time.

Yet, T2 instances can burst higher performance in Unlimited Mode to match spikes in activity, such as a sharp increase in web traffic.

Also, a T2 EC2 instance accumulates credits as long as it performs at or below its baseline performance. The size of a T2 instance determines how many credits it generates each hour.

It then uses those credits in Unlimited Mode (burstable) without incurring additional charges. As soon as those credits run out, and the instance still needs to run in burstable mode, you will be charged $0.05 per hour for the extra resources it consumes.

T2 Instance Size	vCPU	Memory in GiB	Networking Performance	Credits Generated per hour of baseline performance
t2.nano	1	0.5	Low	3
t2.micro	1	1	Low to moderate	6
t2.small	1	2	Low to moderate	12
t2.medium	2	4	Low to moderate	24
t2.large	2	8	Low to moderate	36
t2.xlarge	4	16	moderate	54
t2.2xlarge	8	32	moderate	81

When to use T2 instances:

Typical applications using T2 instances include small and medium line of business apps, web servers, web apps, and development environments.

2. T3 instance type

These General-purpose EC2 instances deliver balanced processing, memory, storage, and networking capabilities, with Unlimited Mode activated by default to provide high-performance bursts.

T3a instances use AMD EPYC 7000 series processors (2.5GHz), while T3 instances use Intel Xeon (Skylake or Cascade) cores (3.1GHz). Both support EBS temporary storage as well as Enhanced Networking.

T3 instances also generate credits when performing at or below baseline to use in burstable mode.

However, a T3 instance can continue to use credits even after it has consumed all accumulated credits. You won’t have to pay extra as long as the instance re-generates the credits owed within 24 hours. Otherwise, you need to pay $0.05 per instance per hour.

T3 Instance Size	vCPU	Memory in GiB	Networking Performance	Credits Generated per hour of baseline performance
t3.nano	2	0.5	Up to 5Ghz	6
t3.micro	2	1	Up to 5Ghz	12
t3.small	2	2	Up to 5Ghz	24
t3.medium	2	4	Up to 5Ghz	24
t3.large	2	8	Up to 5Ghz	36
t3.xlarge	4	16	Up to 5Ghz	96
t3.2xlarge	8	32	Up to 5Ghz	192

When to use T3 instances:

According to AWS, T3 instances offer a 30% price-performance improvement over T2 instances. In addition, it recommends them for small/medium databases, development environments, virtual desktops, and low-latency apps.

3. T4g instance type

This is a newer generation of the T family instance that features AWS’s own, Arm-based Graviton 2 processors (64-bit), which deliver up to 40% better price-performance over T3 instances.

T4 Instance Size	vCPU	Memory in GiB	Networking Performance	Baseline performance to earn credits	Credits Generated per hour of baseline performance
t4.nano	2	0.5	Up to 5Ghz	5%	6
t4.micro	2	1	Up to 5Ghz	10%	12
t4.small	2	2	Up to 5Ghz	20%	24
t4.medium	2	4	Up to 5Ghz	20%	24
t4.large	2	8	Up to 5Ghz	30%	36
t4.xlarge	4	16	Up to 5Ghz	40%	96
t4.2xlarge	8	32	Up to 5Ghz	40%	192

When to use T4g instances:

Business-critical applications, micro-services, small/medium databases and development environments, and virtual desktops.

4. Amazon EC2 M instance types

With M family instances, you get balanced CPU, RAM, and networking capacity, as well as support for EBS and Enhanced Networking. Some instances, like M4, use Intel Xeon processors (scalable and clocked at 2.5GHz), while others, like M6g, use AWS’ Arm Graviton 2 processors.

Newer M instances also come in more sizes than older M4 instances, which only came in six.When to use M instances:

M4 Instance Type	vCPU	Memory in GiB	Networking Performance
m4.large	2	8	Moderate
m4.xlarge	4	16	High
m4.2xlarge	8	32	High
m4.4xlarge	16	64	High
m4.10xlarge	40	160	10 Gbps
m4.16xlarge	64	256	25 Gbps

For workloads that require mostly balanced resources but perform better with extra memory, like cluster computing, mid-size databases, and enterprise apps.

5. A1 instance type

This instance uses AWS Graviton processors, supports Enhanced Networking, EBS storage, and combines lightweight hypervisors and dedicated hardware. There are six sizes to choose from:

A1 Instance Type	vCPU	Memory in GiB	Networking Performance
a1.medium	1	2	Up to 10 Gbps
a1.large	2	4	Up to 10 Gbps
a1.xlarge	4	8	Up to 10 Gbps
a1.2xlarge	8	16	Up to 10 Gbps
a1.4xlarge	16	32	Up to 10 Gbps
a1.metal	16	32	Up to 10 Gbps

When to use A1 instances: Scale-out workloads like web servers, distributed development environments, and containerized apps.

6. Amazon EC2 C instance types

The C family of instances offers high-performance processing power for compute-intensive workloads. You can expect Intel Xeon (C4), AMD SYNC (C5), and AWS Graviton 3 (C7g) processors, enhanced networking, and EBS support. The baseline C4 instances have the following sizes:

C4 Instance Type	vCPU	Memory in GiB	Networking Performance
c4.large	2	3.75	Moderate
c4.xlarge	4	7.5	High
c4.2xlarge	8	15	High
c4.4xlarge	16	30	High
c4.8xlarge	36	60	10 Gbps

When to use Amazon EC2 C instances: Workloads that require high-performance, like batch processing, data analytics, and front-end fleets.

7. Amazon EC2 R instance types

These memory-optimized instances support DDR4 memory, Enhanced Networking, and high frequency processors for running memory-intensive applications.

R6a instances, powered by AMD EPYC processors, deliver up to 60% better price-performance than R4 instances, which are powered by Intel Xeon processors clocked at 2.3Ghz.

Between the two, R5 instances offer the following sizes:

R5 Instance Type	vCPU	Memory in GiB	Networking Performance
r5.large	2	15.25	Up to 10 Gbps
r5.xlarge	4	30.5	Up to 10 Gbps
r5.2xlarge	8	61	Up to 10 Gbps
r5.4xlarge	16	122	Up to 10 Gbps
r5.8xlarge	32	244	10 Gbps
r5.16xlarge	64	488	25 Gbps

When to use Amazon EC2 R instances: High-performance enterprise apps, databases, real-time big data analytics, and Hadoop clusters.

8. Amazon EC2 X instance types

Like R instances, these memory-optimized instances offer varying performance at varying sizes across the X1, X1e, and X2 series. As an example, X2gd instances offer a 55% better price-performance ratio, seven more sizes, and a higher network bandwidth than X1 instances.

As a middle ground, X2iezn instances are available in the following sizes:

X2iezn Instance Type	vCPU	Memory in GiB	Networking Performance
x2iezn.large	8	256	Up to 25 Gbps
x2iezn.xlarge	16	512	Up to 25 Gbps
x2iezn.2xlarge	24	768	50 Gbps
x2iezn.4xlarge	32	1024	75 Gbps
x2iezn.8xlarge	48	1536	100 Gbps
x2iezn.16xlarge	48	1536	100 Gbps

When to use Amazon EC2 X instances: Open-source databases, real-time caching servers, and in-memory cache workloads.

9. Amazon EC2 Z1d instances

If you need both high compute and memory performance, Z1d instances deliver the fastest instance types in the AWS cloud (up to 4.0Ghz in all Intel Xeon cores), up to 384 GiB RAM, and up to 1.8TB storage for each instance. The following sizes are available:

Z1d Instance Type	vCPU	Memory in GiB	Networking Performance
z1d.large	2	16	Up to 10 Gbps
z1d.xlarge	4	32	Up to 10 Gbps
z1d.2xlarge	8	64	Up to 10 Gbps
z1d.3xlarge	12	96	Up to 10 Gbps
z1d.6xlarge	24	192	10 Gbps
z1d.12xlarge	48	384	10 Gbps
z1d.metal	48	384	25 Gbps

When to use Amazon EC2 z1d instance types: relational database use cases with high per core license costs and electronic design automation workloads.

10. Amazon EC2 P instance type

These Accelerated Computing instances provide high performance graphics processing.

P2 instances are ideal for general-purpose GPU workloads, P3 are suitable for high performance compute, while P3 are the latest-generation instances, supporting the highest-performance amongst GPU-based instances.

Here are the size options for P3 instances, as an example:

P3 Instance Type	GPU	GPU Memory	vCPU	Memory in GiB	Networking Performance
p3.2xlarge	1	16	8	61	Up to 10 Gbps
p3.8xlarge	4	64	32	244	10 Gbps
p3.16xlarge	8	128	64	488	25 Gbps
p3.24xlarge	8	256	96	768	100 Gbps

When to use Amazon EC2 P instances: Machine Learning, high performance computing, and more.

Like P instances, G, F1, VT1, DL1, Trn1, and Inf1 instance types are all optimized for GPU-intensive applications. The best thing to do is to check out each instance type individually to see if it suits your needs perfectly.

Speaking of choosing the right EC2 instance type, you can do that either manually or automate the process.

How To Choose The Best EC2 Instances For Your Needs

More than any other AWS service, Amazon EC2 gives you the most choice in the type of instances you choose to launch, run, and maintain your applications.

However, configuring EC2 instance types can be time-consuming, error-prone, and waste a massive amount of resources. For example, by setting just one instance size larger than you require, you can:

It’s a downward spiral that no company wants to experience. You can avoid that with intelligent tools, like CloudZero Advisor.

CloudZero Advisor is a free tool that offers recommendations on the best Amazon EC2 instances for a specific workload by compute instance, pricing, name, release date, architecture, region, compute capacity, and more filters. You can even add a custom filter for even more personalized results.

You can also track Amazon EC2 costs by customer, service, feature, team, project, and more with CloudZero — down to the hour.

Therefore, you can tell who, what, and why your Amazon EC2 costs are changing. This empowers you to tell exactly where to cut costs — or increase investment to maximize ROI.

 to see all this in action within days — not months!