WaterCalcLabWater Pump Flow Calculator
Convert electrical power into a theoretical flow at specified total dynamic head and overall efficiency.
Your result
Bars compare only results in the same unit group. They are normalized, not a time-series forecast.
Planning result based on your inputs.
How this tool works
Convert electrical power into a theoretical flow at specified total dynamic head and overall efficiency.
Q (L/min) = electrical W × η/(1000 × 9.80665 × head m) × 60000Example calculation
The prefilled form is a worked example. Its base-unit inputs and expected outputs are shown below; use the reset button to restore it.
| Input | Example |
|---|---|
| Electrical input power | 500 |
| Total dynamic head | 20 |
| Overall wire-to-water efficiency | 0.5 |
Frequently asked questions
How should I choose the inputs?
Use measurements and local records for the stated period. All preset values are illustrative examples, not recommendations.
What does this result leave out?
Not a pump selection or operating-point prediction. Head includes elevation, pressure and friction. Confirm using manufacturer pump curves, NPSH and system curve.
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Method version 1.0 · Last reviewed: 2026-10-10