AWS t4g vs t3 cost: Graviton burstable instances are ~20% cheaper

Quick answer

t4g instances (AWS Graviton, ARM) cost about 20% less than equivalent t3 (Intel) instances, and often deliver better performance per dollar. Both are burstable, so they share the CPU-credit model. The only catch is that your workload must run on ARM (most modern software does). For ARM-compatible workloads, moving from t3 to t4g is close to free money.

t3 and t4g are AWS's burstable general-purpose instances, identical in the burstable CPU-credit model but different in processor: t3 uses Intel, t4g uses AWS Graviton (ARM). The Graviton version is meaningfully cheaper, so for workloads that run on ARM, t4g is one of the easiest savings on EC2.

About 20% cheaper, per size

For a comparable size, a t4g instance costs roughly 20% less per hour than the equivalent t3. On top of the lower price, Graviton often delivers comparable or better performance for many workloads, so the price-performance gain can exceed the headline 20%. Both share the same burstable model, so CPU credits work the same way, covered in right-sizing EC2 instances.

The compatibility catch

Consideration	Status
Interpreted languages (Python, Node, Ruby, Java)	Run on ARM with no code change
Container images	Need ARM (multi-arch) images
Compiled binaries / native deps	Must be built for ARM
Some proprietary agents	Check ARM support

The workload must run on ARM. For most modern software, interpreted languages, standard container images rebuilt as multi-arch, common databases, this is straightforward. The friction is compiled binaries with x86-only builds and occasional proprietary agents without ARM support. Test the workload on ARM before switching.

When t4g is free money

For ARM-compatible workloads, moving t3 to t4g captures roughly 20% (often more on price-performance) with no downside. Web servers, application servers, and most microservices in interpreted languages or multi-arch containers qualify. Validate compatibility, rebuild containers for ARM, and switch, the same reasoning as the broader Graviton migration savings.

FAQ

How much cheaper is t4g than t3?

About 20% less per hour for a comparable size, and often with comparable or better performance, so the price-performance gain can exceed 20%. Both are burstable instances sharing the same CPU-credit model; the difference is t4g uses AWS Graviton (ARM) versus t3's Intel processor.

What is the catch with t4g instances?

Your workload must run on ARM. Most modern software does, interpreted languages run unchanged, and containers just need ARM (multi-arch) images. The friction is compiled binaries built only for x86 and occasional proprietary agents without ARM support, so test the workload on ARM before switching.

Is moving from t3 to t4g worth it?

For ARM-compatible workloads, yes, it captures roughly 20% (often more on price-performance) with no downside. Web servers, application servers, and most interpreted-language or multi-arch-container microservices qualify. Validate compatibility, rebuild containers for ARM, and switch.

Do I need to change my code to use t4g?

Usually not for interpreted languages like Python, Node, Ruby, and Java, which run on ARM unchanged. Containers need ARM or multi-arch images, and compiled binaries or native dependencies must be built for ARM. Test your specific stack, but most modern software needs no code changes.

Are t4g and t3 the same except for the processor?

In the burstable model, yes, both use CPU credits that accrue when idle and deplete when bursting. The difference is the processor: t4g uses AWS Graviton (ARM) and t3 uses Intel. t4g is cheaper, so for ARM-compatible workloads it is the better-value choice.

Does C3X estimate t4g versus t3 cost?

C3X prices EC2 instances from your Terraform, so you can compare t4g and t3 for the same workload before deploy and see the roughly 20% difference. Whether your workload runs on ARM is a compatibility question you validate separately.

What to do next

Compare instance types for the same workload before you deploy. C3X reads your Terraform and prices your resources against a live catalog. Start with the quickstart.