Well Pump Size Calculator

Estimate well pump size from household water demand, well depth, static water level, drawdown, desired pressure, pipe friction, total dynamic head, pump horsepower, and pressure tank drawdown.

Calculate Well Pump Size

Well Pump Size = Required GPM at Total Dynamic Head.
Your result will appear here.

How the well pump size calculator works

Well pump size:
The calculator estimates required GPM from household demand, fixtures, bathrooms, bedrooms, and a safety factor.

Total dynamic head:
The calculator adds pumping water level, drawdown, pressure head, and estimated pipe friction.

Pump horsepower:
The calculator estimates horsepower from required GPM, total dynamic head, and pump efficiency.

Capacity check:
The calculator compares known pump capacity and well recovery rate against the estimated demand.

Why use a well pump size calculator?

A well pump size calculator helps estimate the pump flow and head rating needed before choosing a well pump.

It can help compare household demand, well depth, static water level, drawdown, pressure head, friction loss, pump horsepower, pressure tank drawdown, and well recovery.

What your result means

Your result shows an estimated well pump GPM, total dynamic head, and horsepower. This is a planning estimate only. Final well pump selection should be checked with a pump curve, well yield test, static and pumping water levels, pressure switch setting, pipe size, voltage, and installer requirements.

Well pump size formulas

Frequently asked questions

How do you size a well pump?

Estimate the required household GPM, calculate total dynamic head, then choose a pump that can deliver that GPM at that head using the pump curve.

What is total dynamic head for a well pump?

Total dynamic head is the pumping water level plus pressure head and pipe friction loss. It represents the resistance the well pump must overcome.

What GPM well pump does a house need?

Many homes are commonly planned around 8 to 12 GPM, but the right size depends on fixtures, bathrooms, demand, well yield, and pressure needs.

Is this well pump calculator exact?

No. This calculator gives a planning estimate. Final well pump sizing should be checked by a well professional using actual well test data and manufacturer pump curves.