Exhaust Fan CFM Calculator

CFM Exhaust Fan Estimator Calculator

To use this cfm calculator, input the type of room you have for your application. This could be selecting an exhaust fan for a warehouse or garage for example. Next, input the dimensions of the room and click “Calculate CFM”. A list of suitable exhaust fans will then appear for your application. Note: All measurements are in feet. Also note that these calculations are only basic guidelines. I recommend choosing a fan with more speed settings in the suitable range for your application of industrial exhaust fans.

How to calculate CFM & CFM calculation formula

In general, to calculate CFM for your industrial exhaust application, you need to know the total floor area of your space. With this number, divide it by multiply it by 0.1 to 1 to get you estimated CFM. For example, a 1000 square foot area may need a CFM exhaust fan of 1000*0.1=100 or 1000*1=1000. This depends on the specific application and the stuffiness, moisture or gases in the air. Refer to the calculator below for more guidance. This may be helpful as a duct cfm calculator, a hvac cfm calculator or an air flow calculator. I have inserted 8 feet as the height for a room as that’s typical. I’ve also added a field of minutes per change, so you don’t have to rely on the preset space in the drop-down menu. E.g If you want to change the air in a room fully every 2 minutes, put 2 in the “Minutes per change” box. This will override the room type.

You can find the full list of industrial and commercial exhaust fans here.

CFM Calculator





cfm calculator fan image

Table data was obtained from Cincinati fan engineering data sheets.