What Size Range Hood Do I Need for My Kitchen?

Measure your cooktop width and add two inches for hood width.

Calculate CFM based on BTU or cooktop width, then adjust for duct length.
Ducted hoods outperform ductless; use a 6-inch duct for up to 600 CFM.
Island and wall-mounted hoods need different CFM and installation considerations.

How to Measure Your Kitchen for a Range Hood

Start with the cooktop width. Standard widths are 30, 36, and 48 inches. The hood should be at least as wide as the cooktop. For better capture, add two to three inches on each side. Measure from the floor to the cooktop to set the mounting height. Most manufacturers recommend 24 to 30 inches above gas and 18 to 24 above electric. Check your ceiling height to ensure clearance.

CFM: How Much Airflow Do You Really Need?

CFM stands for cubic feet per minute. It measures how much air the hood moves. For electric cooktops, use 100 CFM per 10 inches of cooktop width. A 30-inch electric range needs 300 CFM. For gas, calculate based on BTU output. Add up all burners' BTUs and divide by 100. A typical gas range with 40,000 total BTUs needs 400 CFM.

30-Inch vs 36-Inch: Which Hood Width Fits Your Cooktop?

Most residential cooktops are 30 inches wide. A 30-inch hood is the standard choice. For a 36-inch cooktop, choose a 36-inch hood. A wider hood offers better capture but may look oversized. Check your cabinet spacing. Some 30-inch hoods fit into 36-inch openings with filler strips.

Ducted vs Ductless: Does Venting Type Affect Size?

Ducted hoods vent outside through a duct. They are more powerful and quieter. Ductless hoods filter air and recirculate it. They are easier to install but less effective. Duct size matters for performance. Common duct sizes are 6 and 8 inches. A 6-inch duct supports up to 600 CFM. For higher CFM, use an 8-inch duct.

What About Island and Wall-Mounted Hoods?

Island hoods hang from the ceiling. They need higher CFM because they have no wall to help capture. Add 50% to your CFM for island installations. Wall-mounted hoods attach to the wall behind the range. They are common in modern kitchens. Both types come in widths from 24 to 60 inches.

Common questions

How do I determine the right CFM for my range hood?

For gas ranges, add all burner BTUs and divide by 100. For electric, use 100 CFM per 10 inches of cooktop width. For heavy cooking, increase by 50%.

Is a 600 CFM range hood too much for a home kitchen?

Not necessarily. 600 CFM suits large gas ranges or open kitchens. But it may be overkill for small electric cooktops. It can also be noisy and require makeup air.

Can I use a 36-inch hood on a 30-inch cooktop?

Yes, a wider hood works fine. It improves capture and looks balanced. Just ensure it fits your cabinet space.

What is the best height to install a range hood?

For gas cooktops, mount 24 to 30 inches above the surface. For electric, 18 to 24 inches. Check the manufacturer's recommendation for your model.

Do I need a range hood if I have a downdraft vent?

Downdraft vents are less effective than overhead hoods. They work for light cooking. For heavy use, an overhead hood is better.

How do I measure for a range hood replacement?

Measure the width of your cooktop. Then measure the space between cabinets. Also note the duct size and location. Use these to choose a new hood.

What size duct do I need for a 400 CFM range hood?

A 6-inch duct is sufficient for up to 600 CFM. For 400 CFM, 6 inches is standard. If the duct run is long, consider 8 inches.

Are range hoods worth the investment?

Yes, they improve air quality and protect cabinets from grease. They also reduce heat and moisture. Choose the right size for best performance.