This pipeline flow rate calculator finds the volumetric flow rate from the pipe’s inside diameter and the fluid velocity. Enter both values above for the flow in m³/s and L/s.
Formula
Q = A × v = (π ÷ 4) × D² × v
Example
D = 0.1 m, v = 2 m/s: Q = (π/4) × 0.1² × 2 = 0.0157 m³/s (15.7 L/s).
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Frequently Asked Questions
How do I calculate pipeline flow rate?
Multiply the pipe’s cross-section area by the fluid velocity: Q = (pi/4) x D squared x v.
What units does flow rate use?
Cubic meters per second in SI, often shown as liters per second for smaller pipes.
Does this account for friction?
No. It gives the ideal flow from area and velocity; pressure loss needs a separate friction calculation.