Enter the total dynamic pressure and the fluid mass density into the calculator to determine the velocity. This calculator can also evaluate the pressure or density given the other variables are known.

Pressure to Velocity Formula

The following formula is used to calculate a velocity from dynamic pressure.

V = Sqrt [ (2*q/p) ] 
  • Where V is the velocity (m/s)
  • q is the dynamic pressure (pascals)
  • p is the fluid mass density (kg/m^3)

To calculate velocity from pressure, multiply the dynamic pressure by 2, divide by the fluid mass density, then take the square root of that result.

Pressure to Velocity Definition

Calculate a velocity from a dynamic pressure requires that you also know the density. Dynamic pressure arises from the movement of fluid through a volume.

Pressure to Velocity Example

How to calculate velocity from pressure?

The first step in calculating a velocity from pressure is to determine or measure the dynamic pressure that happens as a result of the fluid flow through the pipe.

In this example, the dynamic pressure is found to be 200 pascals.

The next step is to determine the density of the fluid. In this case, the density is measured to be 1.225 kg/m^3.

Finally, calculate the velocity from the dynamic pressure and density using the formula above:

V = Sqrt [ (2*q/p) ]

V = Sqrt [ (2*200/1.225) ]

V = 18.07 m/s.


What is a dynamic pressure?

Dynamic pressures are pressure differentials that arise from the flow of a fluid through a constrained area.