How this calculator works
Enter peak requests/s, requests/s per instance, headroom (%), availability zones. CalcStack applies the displayed formula and reports each intermediate planning value with the units shown.
Formula / method
Instances = ceil(peak RPS × headroom ÷ instance RPS)
Worked example
Use the documented default inputs to model load balancer capacity.
Assumptions and limitations
Inputs represent stable average operating conditions and the displayed equation applies.
This is a planning model; real systems and measurements can require domain-specific corrections.