Fluid Flow Calculator
Volumetric flow rate from pipe diameter and velocity — Q = A · v.
How to Use
- Enter pipe inner diameter and fluid velocity.
- Flow rate, Reynolds number, and regime appear.
Pipe + fluid
Flow
Formulas
Area
A = π · (d/2)²
Flow rate
Q = A · v
Reynolds
Re = v · d / ν
Regime
< 2 300 laminar · > 4 000 turbulent
Last updated: