Compare Aurora Standard against Aurora I/O-Optimized on instance, storage and I/O charges, and find the break-even I/O volume.
An Aurora Standard bill has a variable third component: every 8 KB page the storage layer reads or writes is a billable I/O request, so an I/O-heavy workload can spend more on I/O than on compute. I/O-Optimized trades that variability for a flat surcharge on instance and storage rates, and the break-even output is simply the extra fixed cost divided by the per-million I/O price. All rates are editable inputs with realistic us-east-1 defaults, so confirm current prices with AWS for your region. AWS suggests I/O-Optimized pays off once I/O is more than roughly 25% of the Aurora bill, and this is the arithmetic behind that rule of thumb for your own numbers.
Aurora Cost
Standard = instances × hourly × hours + GB × 0.10 + I/O millions × 0.20. I/O-Optimized = instances × hourly × hours × (1 + uplift) + GB × 0.225, with no I/O charge.
Standard = instances × hourly × hours + GB × 0.10 + I/O millions × 0.20. I/O-Optimized = instances × hourly × hours × (1 + uplift) + GB × 0.225, with no I/O charge. An Aurora Standard bill has a variable third component: every 8 KB page the storage layer reads or writes is a billable I/O request, so an I/O-heavy workload can spend more on I/O than on compute. I/O-Optimized trades that variability for a flat surcharge on instance and storage rates, and the break-even output is simply the extra fixed cost divided by the per-million I/O price. All rates are editable inputs with realistic us-east-1 defaults, so confirm current prices with AWS for your region.
AWS suggests I/O-Optimized pays off once I/O is more than roughly 25% of the Aurora bill, and this is the arithmetic behind that rule of thumb for your own numbers.
This calculator takes 10 inputs: Instance price, Read replicas, Billed hours per month, Cluster volume in use, Standard storage price, I/O requests per month, I/O price, Use Aurora I/O-Optimized, I/O-Optimized instance uplift, I/O-Optimized storage price. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
Yes — each Aurora Replica is billed as a full instance. Replicas share the cluster volume so they add no storage cost, but their queries do generate billable read I/O on Aurora Standard.
They are realistic us-east-1 defaults only. Aurora rates vary by region, engine and instance family, so confirm each figure against the AWS Aurora pricing page for your region before quoting a budget.