Pump Head Calculator

About this calculator

Total dynamic head (TDH) is the total resistance a pump must overcome to move fluid, expressed as an equivalent height of liquid rather than a pressure. It’s the sum of three parts: static head (the actual elevation the fluid must be lifted), friction head loss (energy lost to pipe friction, fittings and valves along the way), and velocity head (V²/2g, the energy needed to give the fluid its exit speed).

Pump manufacturers publish performance curves in terms of head versus flow rate, so knowing a system’s TDH — in metres, feet or the equivalent psi — is essential to reading that curve correctly and picking a pump that neither struggles to deliver the required flow nor wastes energy oversized for the job. Mechanical and civil engineers, irrigation designers and pump-system installers calculate TDH when sizing pumps for water supply, HVAC, wastewater and irrigation systems.