ACH Calculator

Air Changes per Hour (ACH):


Calculate The Air Change Per Hour Of Your Desired Space And Obtain Optimal Ventilation For Your Environment

Use the above ACH Calculator to get an accurate reading of your space’s air change per hour requirements.

What Is ACH?

ACH indicates the air changes per hour. It simply means the frequency at which the air inside a room or space is replaced with fresh air in one hour. For example, if the ACH is 3, it signifies that the air inside the space is replaced with fresh air three times in one given air. 

Having a greater ACH is preferred because it signifies better ventilation, which helps maintain better air circulation and quality whilst ensuring comfort and safety. 

Why Do You Need An ACH Calculator?

ACH calculator helps you attain a comfortable environment with proper ventilation. To maintain perfect air quality of your surroundings, you need to know the required ACH of your room. Knowing this parameter can help you purchase the appropriate ventilation unit, and maintain sufficient air flow along with maximum energy consumption. 

Our free ACH calculator helps you calculate the accurate air change per hour requirement so that you can purchase the right ventilation system for your needs. Using our calculator is simple. All you need to know is the volume of the room you want to calculate the ACH of, and the airflow rate in CFM. 

How To Calculate ACH?

To calculate the ACH of a given room with the help of our calculator, you need:

Airflow Rate in CFM: the capacity of your HVAC system to move a certain volume of air within it in a minute. 

Volume of the room: to calculate the volume of the room, you need to know the length, width and height of it. 

The formula for calculating the ACH of your room, 

(CFM * 60) / Volume

Here, 60 is s a conversion factor that converts cubic feet per minute (CFM) to cubic feet per hour

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