Estimate sprinkler flow from the metric K-factor and the pressure at the head in bar.
| Flow | – |
Use this calculator for a first flow at a sprinkler. Enter the metric K stamped on the head and the residual pressure in bar.
Q (L/min) = K × √P, with P in bar. Flow is shown in litres per minute (L/min) or gallons per minute (gpm). Pressure stays in bar. A standard spray K might be around 80 (L/min)/√bar. This is not an imperial K (gpm/√psi).
This is a single-head orifice formula. It is not a full hydraulic calculation of a grid.
K (metric): K-factor as stamped, in (L/min)/√bar.
Pressure (bar): Pressure at the sprinkler in bar. 1 bar ≈ 10 m of head.
Flow: Discharge in L/min or gpm.
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