How to use the volumetric flow rate calculator
Compute flow rate from pipe size and fluid speed. Enter pipe diameter, fluid speed in the fields above; the flow rate, flow rate, flow rate are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- D — Pipe diameter (cm)
- v — Fluid speed (m/s)
Worked example
With pipe diameter = 2.5 cm, fluid speed = 2 m/s, the calculator gives flow rate ≈ 58.90486 L/min; flow rate ≈ 0.00098175 m³/s; flow rate ≈ 15.56102 US gal/min.
Frequently asked questions
What is the formula for the volumetric flow rate calculation?
Flow rate (L/min) = π × (D / 200)^2 × v × 60000. Flow rate (m³/s) = [Flow rate] / 60000. Flow rate (US gal/min) = [Flow rate] × 0.264172. Here D is pipe diameter (cm), v is fluid speed (m/s).
What inputs do I need for the volumetric flow rate calculator?
You need pipe diameter in cm, fluid speed in m/s. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.