Well Pump and System Flow Rate (GPM) Calculator
Estimate the minimum peak flow rate your well system needs to support.
15+
Minimum Required Peak Flow Rate
8 GPM
Any backwashing filter or softener on this system (iron filters, water softeners, sediment filters) must be sized to sustain this flow rate without a pressure drop. An undersized backwash valve is one of the most common causes of low water pressure complaints on well systems.
This is a planning estimate, not a hydraulic engineering calculation. For pump replacement or new well design, confirm sizing with a licensed well contractor.
Related Sizing and Buying Guides
- Sizing a sediment filter for your flow rateHousing size by GPM, so the filter does not choke pressure.
- Matching a softener valve to your peak flowWhy valve flow ratings matter as much as grain capacity.
- Water softener size calculatorGrain capacity from hardness, iron and household size.
- Planning a whole house filtration systemEvery stage has to be rated for your peak GPM.
- Low pressure? Well pump repair costsWhen the flow problem is the pump, not the filters.