Free Ceiling Fan Tools

Our tools run in your browser, need no sign-up and show the rules they use, so you can check the result yourself.

• Ceiling fan size calculator: enter your room’s length and width (or square footage) and ceiling height to get the recommended blade span, a target airflow range in CFM and the downrod length that puts the blades at the right height.

What the calculator answers

Question	What you enter	What you get
What size ceiling fan do I need?	Room length and width, or square feet	Recommended blade span
How much airflow should the fan move?	Room size	Target airflow range in CFM
Do I need a downrod, and how long?	Ceiling height	Mount type and downrod length for the right blade height

Every result shows the rule behind it, taken from published guidance by ENERGY STAR, the US Department of Energy and fan makers’ installation manuals. See how we research for the sources we rely on.

Guides that go with the tools

• Ceiling fan size guide: blade span by room size, number of blades and when a long room needs two fans.
• Ceiling fan height: the 7 ft minimum blade height, ceiling and wall clearances, and when a flush mount makes sense.
• How much electricity a ceiling fan uses: watts by speed and what a fan costs to run per month.
• Ceiling fan direction: which way the blades should spin in summer and winter.

Important: the calculator sizes the fan, not the wiring. Before you hang a fan, turn off the breaker, make sure the ceiling box is rated for fan support, follow the manual and local code, and call a licensed electrician if you’re unsure.