T3 instances are designed to run the majority of general purpose workloads at a much lower cost. T3 instances work by providing a baseline level of CPU performance to address many common workloads while providing the ability to burst above the baseline for times when more performance is required. T3 instances makes use of credits to track how much CPU is used. T3 instances accumulate CPU credits when a workload is operating below the baseline threshold and uses credits when running above the baseline threshold. T3 instances are unlike any other burstable instance available in the market today since customers can sustain high CPU performance, whenever and however long required.

T3 instances start in Unlimited mode by default, giving users the ability to sustain high CPU performance over any desired time frame while keeping cost as low as possible. For most general-purpose workloads, T3 Unlimited instances provide ample performance without any additional charges. If the average CPU utilization of a T3 instance is lower than the baseline over a 24-hour period, the hourly instance price automatically covers all interim spikes in usage. In the cases that the T3 instances needs to run at higher CPU utilization for a prolonged period, it can do so for a small additional charge of $0.05 per vCPU-hour. You can also choose to run in Standard Mode where a T3 instance can burst until it uses up all of its earned credits. For more details on T3 credits, please see the EC2 documentation page.

T3 instances feature either the 1st or 2nd generation Intel Xeon Platinum 8000 series processor (Skylake-SP or Cascade Lake) with a sustained all core Turbo CPU clock speed of up to 3.1 GHz, and deliver up to 30% improvement in price performance compared to T2 instances. T3 instances provide support for the new Intel Advanced Vector Extensions 512 (AVX-512) instruction set, offering up to 2x the FLOPS per core compared to the previous generation T2 instances. T3a instances feature the AMD EPYC 7000 series processor with an all core turbo clock speed of up to 2.5 GHz. T3a offers a 10% lower price than T3 instances for customers who are looking to further cost optimize their Amazon EC2 compute environments.

T3 instances are built on the AWS Nitro System, a rich collection of building blocks that offloads many of the traditional virtualization functions to dedicated hardware. By doing so, the AWS Nitro System enables high performance, high availability, and high security while also reducing virtualization overhead.