Ceiling Fan Size & CFM Calculator (Bedroom)
Choose the right ceiling fan for comfort and airflow. Enter your room size and ceiling height to get a suggested blade span range, a target airflow in CFM (and m³/h), and a downrod length so the blades sit at a safe, efficient height. These are rules of thumb—always check manufacturer specs and local codes.
How to use
- Choose units (Metric or Imperial).
- Enter room length × width and your ceiling height.
- Select your preferred breeze level (quiet → airy) and optional climate bump.
- Click Calculate to see blade span, target CFM (and m³/h), and downrod suggestion.
Worked example
Bedroom 3.6 m × 3.0 m (≈ 11 m²), ceiling 2.7 m, breeze Standard, climate Temperate.
- Area ≈ 118 ft² → blade span 42–48″
- Target airflow: 118 × 20 ≈ 2,360 CFM (≈ 4,010 m³/h)
- Downrod: aim blades ≈ 8 ft from floor → suggest 6–12″ downrod (model‑dependent)
Ceiling fan sizing calculator
FAQs
What blade span do I need for a bedroom?
As a guide: up to 75 ft² → 29–36″; 76–100 ft² → 36–42″; 101–150 ft² → 42–48″; 151–300 ft² → 50–56″; larger → 60–72″ or multiple fans.
How much CFM should I target?
Comfort depends on climate and preference. A simple target is 20 CFM per ft² for most bedrooms; go up to 25–30 CFM/ft² in hotter regions or if you like a stronger breeze.
What downrod length is best?
Fans work best with blades around 8–9 ft from the floor. Short ceilings often need flush mounts; taller ceilings may need a 6–24″ downrod. Check your fan’s specific drop and clearance.
Can I use this for living rooms too?
Yes, but larger rooms may need bigger spans and higher CFM, or multiple fans for even coverage.