Friction Loss Calculator

Hose Diameter

Hose Length (feet)

Flow Rate (GPM)


Friction Loss:{{ output_frictionloss }} PSI

A {{ output_length }} foot length of {{ output_hosesize }} inch hose flowing {{ output_gpm }} GPM has {{ output_frictionloss }} PSI friction loss.

Friction Loss Explained

Friction loss occurs when water passes through a hose. Hose length, diameter, and GPM (volume) all affect friction loss. As water passes through a hose, friction between the water and the inside surface of the hose causes turbulence, which slows the water. The results in a PSI drop (pressure loss) at the other end of the hose. The higher the gpm passing through a hose, the more turbulance and friction loss will result.

Friction loss examples:

100 ft 1" @ 100 gpm = 150 PSI
100 ft 1 1/2" @ 100 gpm = 24 PSI
100 ft 1 3/4" @ 150 gpm = 34.88 PSI
200 ft 1 3/4" @ 150 gpm = 69.75 PSI
100 ft 1 3/4" @ 185 gpm = 53.05 PSI
200 ft 1 3/4" @ 185 gpm = 106.1 PSI
100 ft 1 3/4" @ 200 gpm = 62 PSI
200 ft 1 3/4" @ 200 gpm = 124 PSI
100 ft 2 1/2" @ 150 gpm = 4.5 PSI
100 ft 2 1/2" @ 200 gpm = 8 PSI
100 ft 2 1/2" @ 300 gpm = 18 PSI
200 ft 2 1/2" @ 300 gpm = 36 PSI

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