// Free Engineering Tool

Pump & Fan Power Calculator

Calculate hydraulic power, shaft (absorbed) power and motor sizing for pumps and fans. Enter flow rate and either total head or pressure rise, set fluid density and efficiencies, and get power in kW instantly — with a service-factor installed rating and an efficiency sensitivity table. Verified against standard formulae.

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Duty & Fluid

Fluid Preset

Flow Rate

m³/h

Total Head

Pressure Rise

Fluid Density

kg/m³

Pump Efficiency

Motor Efficiency

Service Factor

Hydraulic power P_h = ρ·g·Q·H. Shaft power = P_h / pump efficiency. Motor input = shaft / motor efficiency. Installed applies the service factor. For fans, enter pressure rise in Pa; the tool converts to equivalent head. Preliminary sizing — confirm against pump/fan curves.

Results

Shaft Power (Absorbed)—

Installed (with Service Factor)—

Hydraulic Power—

Motor Input Power—

Equivalent Head—

Flow (L/s)—

Power vs Efficiency — Current Duty

Pump η	Shaft (kW)	Motor (kW)	Installed (kW)

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