Hydraulic Power Calculator
Find hydraulic and required input power from pressure and flow.
Results
Hydraulic power
- Required shaft input power
- 10 kW13.41 hp
Use the pressure difference across the pump, not an unrelated gauge reading. Overall pump efficiency differs from volumetric efficiency. Electric motor losses and service margins are not included in the shaft input result.
Formula · How it works
Formula
Pₕ = p × Q; Pᵢₙ = Pₕ / ηHydraulic power Pₕ = pQ in W when pressure is in Pa and flow is in m³/s. Equivalently, Pₕ(kW) = pressure(bar) × flow(L/min) / 600. Shaft input power Pᵢₙ = Pₕ/η, where 85% efficiency is 0.85. hp means mechanical horsepower (approximately 745.6999 W); GPM means US gallons per minute.
Worked example
At 100 bar and 60 L/min, hydraulic power is 100 × 60 / 600 = 10 kW (13.41 hp). At 85% overall pump efficiency, required shaft input power is 10 / 0.85 = 11.76 kW.
How it works
Pressure multiplied by volumetric flow is the power delivered to the fluid. Pump losses mean the shaft must supply more power than reaches the fluid. Dividing by overall pump efficiency accounts for those losses.
Common questions
Which efficiency should I enter?
Use overall pump efficiency at the operating point, including volumetric and mechanical losses. Volumetric efficiency alone is insufficient for estimating shaft input power.
Is required input power the electrical supply power?
No. It is mechanical power at the pump shaft. To estimate electrical input, divide shaft input power by the electric motor's efficiency and account for other drive losses.