AWS d3en.2xlargevsAWS d3en.4xlarge

d3en.2xlarge pairs 8 vCPUs with 32GB of RAM at $1.0510/hr On-Demand (about $757/mo at 24×7). d3en.4xlarge pairs 16 vCPUs with 64GB at $2.1030/hr (~$1514/mo). d3en.2xlarge is 100% cheaper per hour than d3en.4xlarge ($1.0520/hr gap).

Because both instances are in the **d3en family**, the only thing that changes between them is sizing — same silicon, same architecture (Intel Xeon (x86_64)), same burstable/sustained behavior. The choice is purely about how much capacity you actually need: d3en.2xlarge gives you 8 vCPUs and 32GB of RAM, d3en.4xlarge gives you 16 vCPUs and 64GB. AWS scales pricing close to linearly within a family, so picking the right size is mostly about right-sizing your workload, not getting a better deal per vCPU.

On raw price-per-performance, the two are d3en.2xlarge delivers ~107% more single-thread Sysbench score per dollar (1040 vs 503 points per $1/hr). That's the cleanest signal we have for "which one runs your workload faster per dollar," but it only matters if your workload is single-thread-bound; for parallel workloads the multi-core scores (6685 vs 13032) are what to weigh. Spot pricing flips many of these comparisons — when d3en.2xlarge drops to $0.2179/hr and d3en.4xlarge drops to $0.5310/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick d3en.2xlarge when your workload is closer to storage-optimized (HDD) (dense, sequential HDD storage — HDFS, MapReduce, log warehouses). Pick d3en.4xlarge when it's closer to storage-optimized (HDD) (dense, sequential HDD storage — HDFS, MapReduce, log warehouses). When neither side is obviously right, the cheaper hourly rate usually wins for fault-tolerant batch workloads, while the higher single-core score usually wins for latency-sensitive web traffic. The regional pricing tables linked from each instance page below show where each is currently cheapest — sometimes a >20% regional gap flips the comparison entirely.