Homeowners find it difficult to choose the correct size of air conditioner that is suitable for their specific needs. Considering that only the right size of AC unit could efficiently and effectively keep you and your loved ones comfortable, choosing the suitable size for your room is very important.  Keep in mind that installing a too big air conditioner unit use more electricity while having a too small unit could not provide your room the comfortable temperature.

Below are the factors you must consider in order to get the correct size for your room.

AC Sizing


  • If the room is very sunny, increase the size by 10%. If it is very shady, decrease the size by 10%.
  • If more than two people regularly occupy the room, add 600 BTUs per hour for each additional person to the size selected.
  • If your room air conditioner is intended for use in a kitchen, increase size by 4,000 BTUs per hour.


Photo and Information source: Efficiency Vermont