Calculate estimated friction loss in a water pipe based on flow rate, inside pipe diameter, pipe length, and pipe material. Estimate PSI loss, head loss, friction loss per 100 feet, water velocity, equivalent length, and outlet pressure.
Total friction loss:
The calculator estimates friction loss through the pipe using a Hazen-Williams style water flow equation.
Loss per 100 feet:
The calculator divides total friction loss by equivalent pipe length and scales the result to 100 feet.
Outlet pressure:
The calculator subtracts friction loss and elevation change from starting pressure to estimate remaining pressure.
A friction loss calculator helps estimate how much pressure is lost as water moves through pipe, fittings, valves, and long runs.
It can help compare PSI loss, head loss, loss per 100 feet, water velocity, flow rate, pipe diameter, equivalent length, and outlet pressure.
Your result shows estimated friction loss through the pipe, friction loss per 100 feet, head loss, water velocity, equivalent length, and outlet pressure. These are planning estimates only. Real systems can vary based on fittings, valves, filters, pipe condition, pipe material, water temperature, elevation, and system layout.
Friction loss is pressure lost as water rubs against the inside of a pipe and passes through fittings, valves, and restrictions.
Higher flow, smaller pipe diameter, longer pipe length, rougher pipe material, valves, filters, and fittings can all increase friction loss.
Yes. Larger pipe usually lowers water velocity and friction loss for the same flow rate.
No. This calculator provides a planning estimate. Final design should account for actual pipe data, fittings, valves, elevation, local code, and complete system requirements.