Pump Power Calculator
The pump power estimator calculates hydraulic power from flow, total dynamic head and fluid density, then estimates input power using a supplied overall efficiency.
How to use this calculator
- Enter flow in litres per minute, total dynamic head in metres, fluid density and efficiency percentage.
- Check the units and definitions before comparing results with another source.
- Change one input at a time when comparing scenarios, and keep the reporting period and assumptions consistent.
Formula used by the pump power calculator
Phydraulic = ρgQH; Pinput ≈ Phydraulic/efficiency
- Phydraulic = ρgQH; Pinput ≈ Phydraulic/efficiency
- Actual pump performance depends on the pump curve, pipe friction, fittings, fluid conditions and operating point. It is not a final equipment specification.
- Inputs are checked for required values and valid ranges; displayed results are rounded for readability.
Worked examples
Worked example
60 litres per minute pumped through 10 m of head with water density 1,000 kg/m³ and 60% efficiency.
Hydraulic output is about 98.1 W; input power estimate is about 163.4 W.
Hydraulic output is about 98.1 W; input power estimate is about 163.4 W.
Understanding the result
The pump power estimator calculates hydraulic power from flow, total dynamic head and fluid density, then estimates input power using a supplied overall efficiency.
Actual pump performance depends on the pump curve, pipe friction, fittings, fluid conditions and operating point. It is not a final equipment specification.
Important notes
Actual pump performance depends on the pump curve, pipe friction, fittings, fluid conditions and operating point. It is not a final equipment specification.
The result applies to the numbers and assumptions entered here; verify specifications for safety-critical or regulated uses.
Frequently asked questions
What is total dynamic head?
It combines the lift and other head requirements used in the pump-system calculation; pipe and fitting losses should be included in the entered value.
Can I use hydraulic power as the motor rating?
No. Input power exceeds hydraulic output by losses, and actual motor sizing needs appropriate service margins and manufacturer data.
How do I use this calculator?
Enter flow in litres per minute, total dynamic head in metres, fluid density and efficiency percentage.
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- Electrical Power Calculator — Calculate electrical power from voltage and current, with an optional power factor.
- Pipe Flow Velocity Calculator — Estimate average flow velocity in a circular pipe from a volumetric flow rate and internal diameter.
- Three-Phase Power Calculator — Estimate apparent power, active input power and output power for a balanced three-phase system.
Related explanations
Learn the method behind the number or compare the terminology before using the calculator.
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.