Effective cores
2.8
CPU Capacity Calculator
Turn a measured RPS-per-core benchmark into a throughput estimate while keeping an explicit CPU utilization target.
Free · no login · browser-based
CPU capacity
Result
Estimated max RPS
336
How it works
This calculator converts the CPU core budget and target utilization into effective compute, then applies an RPS-per-core value measured with the same workload and infrastructure class.
Formula
effective_cores = total_cores * utilization_pct
max_rps = effective_cores * rps_per_coreDerive RPS per core from a representative load test. Re-benchmark when the code path, dependencies, runtime limits or instance family changes.
Example
With 8 cores, a 70% target and 120 measured RPS/core, effective compute is 5.6 cores and estimated capacity is 672 RPS.
FAQ
Is RPS per core fixed?
No. It changes with the code path, runtime, database and downstream latency, caching and compute generation.
Can I use vCPU?
Yes, when both the benchmark and the target environment use the same compute definition and comparable infrastructure.
Why preserve CPU headroom?
Headroom absorbs short bursts, background work and estimation error. A throughput estimate at 100% CPU is not a resilient operating target.
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Important note
This is a capacity model, not a production guarantee. Confirm the result with a representative benchmark and observe latency, saturation and error rate together.