What Size Bathroom Fan (CFM)?
Quick answer
Eight air changes an hour — sized for your actual bathroom.
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Figures are estimates from this calculator’s standard formula — adjust the inputs in the tool below for your exact number.
What Size Bathroom Fan (CFM)?
Eight air changes an hour — sized for your actual bathroom.
Step 1 of 2
The roomFloor size and ceiling — that is the whole air volume.
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ft
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