AWS c6in.4xlargevsAWS c6in.xlarge

c6in.4xlarge pairs 16 vCPUs with 32GB of RAM at $0.9072/hr On-Demand (about $653/mo at 24×7). c6in.xlarge pairs 4 vCPUs with 8GB at $0.2268/hr (~$163/mo). c6in.xlarge is 75% cheaper per hour than c6in.4xlarge ($0.6804/hr gap).

Because both instances are in the **c6in 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: c6in.4xlarge gives you 16 vCPUs and 32GB of RAM, c6in.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 c6in.xlarge delivers ~301% more single-thread Sysbench score per dollar (3280 vs 13139 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 (24779 vs 6179) are what to weigh. Spot pricing flips many of these comparisons — when c6in.4xlarge drops to $0.3057/hr and c6in.xlarge drops to $0.0759/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick c6in.4xlarge when your workload is closer to compute-optimized (CPU-bound work — batch processing, web servers under sustained load, game servers). Pick c6in.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.