Flow Rate Calculator
Calculate the volumetric flow rate of a fluid through a pipe or channel from the cross-sectional area and flow velocity (Q = A × v).
- Liters per second
- 100.00 L/s
Formula: Q = A × v
About Flow Rate Calculator
Flow Rate Calculator is a free online calculator that gives you an instant, accurate result as you type. Calculate the volumetric flow rate of a fluid through a pipe or channel from the cross-sectional area and flow velocity (Q = A × v).
The calculation uses the standard formula Q = A × v and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
The continuity equation follows from this relation: when a pipe narrows, the fluid must speed up to keep the same flow rate.
Frequently Asked Questions
Is Flow Rate Calculator free to use?
Yes. Flow Rate Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (Q = A × v) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
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