AWS c8gn.largevsAWS c8gn.xlarge

c8gn.large pairs 2 vCPUs with 4GB of RAM at $0.1185/hr On-Demand (about $85/mo at 24×7). c8gn.xlarge pairs 4 vCPUs with 8GB at $0.2370/hr (~$171/mo). c8gn.large is 100% cheaper per hour than c8gn.xlarge ($0.1185/hr gap).

Because both instances are in the **c8gn 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: c8gn.large gives you 2 vCPUs and 4GB of RAM, c8gn.xlarge gives you 4 vCPUs and 8GB. 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 c8gn.large delivers ~100% more single-thread Sysbench score per dollar (28169 vs 14072 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 (6518 vs 13186) are what to weigh. Spot pricing flips many of these comparisons — when c8gn.large drops to $0.0349/hr and c8gn.xlarge drops to $0.0738/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick c8gn.large when your workload is closer to compute-optimized (CPU-bound work — batch processing, web servers under sustained load, game servers). Pick c8gn.xlarge 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.