Pipe Flow Velocity Calculator
Calculate water velocity for multiple flow and internal-diameter pairs in one reviewable list.
What would you like to do next?
Screen multiple pipe lines with the same visible equation
List each line with flow in litres per second and actual internal diameter in millimetres. The calculator converts the units, derives circular cross-sectional area and divides volumetric flow by area. Each result keeps the entered line name, flow, diameter and velocity together for comparison.
Use velocity as one input to hydraulic design
A velocity result does not show pressure loss, static pressure, surge, pump interaction, air release, noise, erosion or water-age effects. Nominal pipe size may differ from internal diameter by material and pressure class. Confirm the network model, pipe data, operating envelope and applicable design criteria.
Frequently asked questions
Does the tool use nominal pipe size?
No. Enter the actual internal diameter in millimetres.
How is area calculated?
The tool uses the circular area from the entered diameter.
Is a velocity result a pipe-size approval?
No. Full hydraulic and engineering checks remain necessary.