AWS c6gn.2xlargevsAWS c6gn.4xlarge

c6gn.2xlarge pairs 8 vCPUs with 16GB of RAM at $0.3456/hr On-Demand (about $249/mo at 24×7). c6gn.4xlarge pairs 16 vCPUs with 32GB at $0.6912/hr (~$498/mo). c6gn.2xlarge is 100% cheaper per hour than c6gn.4xlarge ($0.3456/hr gap).

Because both instances are in the **c6gn family**, the only thing that changes between them is sizing — same silicon, same architecture (AWS Graviton (ARM64)), same burstable/sustained behavior. The choice is purely about how much capacity you actually need: c6gn.2xlarge gives you 8 vCPUs and 16GB of RAM, c6gn.4xlarge gives you 16 vCPUs and 32GB. 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 c6gn.2xlarge delivers ~100% more single-thread Sysbench score per dollar (8137 vs 4061 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 (22192 vs 44674) are what to weigh. Spot pricing flips many of these comparisons — when c6gn.2xlarge drops to $0.1471/hr and c6gn.4xlarge drops to $0.2124/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick c6gn.2xlarge when your workload is closer to compute-optimized (CPU-bound work — batch processing, web servers under sustained load, game servers). Pick c6gn.4xlarge when it's closer to compute-optimized (CPU-bound work — batch processing, web servers under sustained load, game servers). 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.