AWS r7i.largevsAWS r7i.xlarge

r7i.large pairs 2 vCPUs with 16GB of RAM at $0.1323/hr On-Demand (about $95/mo at 24×7). r7i.xlarge pairs 4 vCPUs with 32GB at $0.2646/hr (~$191/mo). r7i.large is 100% cheaper per hour than r7i.xlarge ($0.1323/hr gap).

Because both instances are in the **r7i 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: r7i.large gives you 2 vCPUs and 16GB of RAM, r7i.xlarge gives you 4 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 r7i.large delivers ~100% more single-thread Sysbench score per dollar (24747 vs 12400 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 (3350 vs 6722) are what to weigh. Spot pricing flips many of these comparisons — when r7i.large drops to $0.0434/hr and r7i.xlarge drops to $0.0775/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick r7i.large when your workload is closer to memory-optimized (memory-bound work — in-memory databases, real-time analytics, large caches). Pick r7i.xlarge when it's closer to memory-optimized (memory-bound work — in-memory databases, real-time analytics, large caches). 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.