Enter the differential pressure (W.C.) and the cross-sectional area (ft^2) into the CFM From Differential Pressure Calculator. The calculator will evaluate the CFM From Differential Pressure.

## CFM From Differential Pressure Formula

The following two example problems outline the steps and information needed to calculate the CFM From Differential Pressure.

CFM = 4005 * SQRT( dP) * A

Variables:

- CFM is the CFM From Differential Pressure (ft^3/min)
- dP is the differential pressure (W.C.)
- A is the cross-sectional area (ft^2)

To calculate CFM from differential pressure, multiply the square root of the pressure by the area, then multiply again by 4005.

## How to Calculate CFM From Differential Pressure?

The following steps outline how to calculate the CFM From Differential Pressure.

- First, determine the differential pressure (W.C.).
- Next, determine the cross-sectional area (ft^2).
- Next, gather the formula from above = CFM = 4005 * SQRT( dP) * A.
- Finally, calculate the CFM From Differential Pressure.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

differential pressure (W.C.) = .50

cross-sectional area (ft^2) = 2.5

CFM = 4005 * SQRT( dP) * A** **= ?