Grow Room Fan Calculator

Please enter details in the field and the results will be displayed below.

Grow Room Size

Fan Parameters



Total air replacement in your grow room is every:

{{amount}} minutes

Good, your air replacement rate is under 2 minutes which is ideal for plants. The recommended air replacement rate is 2 minutes or less.

Warning, your air replacement rate is over 2 minutes, you should increase the airflow in your grow room. The recommended air replacement rate is 2 minutes or less, this is ideal for plants.

In smaller environments with high light levels (high heat output in a confined environment) you will ideally want to increase the airflow levels to ensure complete air replacement every 30 seconds. This is due to heat rising significantly faster in smaller environments. Eg. a closet with a 600 watt light etc.



Bigger filters represent better value for money in the long term and allow for better airflow (less percentage of air loss with the same fan).


Larger filters require less pressure than smaller filters because there is a greater surface area for the same volume of air to move through.


For approximately 30-35% more retail cost you can purchase twice the carbon (ie. twice the life span) and improve your airflow too.

Fan Speed Converter

Convert fan speeds between units by filling in one field.

Other Ventilation Information

The tighter the bends are in your ducting, the lower the ventilation flow will be. Try to smooth out your bends as much as possible, and make them more gentle to increase flow.