Best Bathroom Exhaust Fans of 2024

A bathroom exhaust fan works by pulling in air from the bathroom and sending it outside via a duct that runs through the ceiling or wall. So a good exhaust fan relies largely on good airflow. Good airflow, in turn, depends on the ductwork in your bathroom, as well as the speed of the fan.

The more bends there are in the duct, the more resistance there will be to the airflow—so to a large extent, the effectiveness of your exhaust fan will depend on the shape of the ductwork in your home. The size of your duct also matters. Bathroom exhaust fans are designed to fit a particular duct size. Generally, fans built for larger air ducts produce better airflow. Newer bathrooms tend to have vents with 4-inch ducts or larger, while older-bathroom vents tend to have 3-inch ducts. You can renovate to upgrade your duct size, though that will require professionals and a chunk of money. More importantly, if you have a smaller bathroom (around 50 square feet or smaller), that smaller duct size—and the fans built for it—may work quite effectively for you anyway.

As for a fan’s speed, it’s a measurement of airflow velocity in CFM. The fans we tested (like most fans on the market) run at only one speed. (One fan we tested, the Panasonic WhisperFit DC, above, does offer three speeds. But you make the choice when you install it, so when you hit the switch, it will run at the speed you chose during installation.) While it may seem logical that a fan running at a higher speed trumps a fan at a lower speed, you might not see that big a difference in effectiveness between the two, especially in a smaller bathroom. A higher fan speed could also be noisier.

Under the wrong conditions, the warm, moist air produced by showers and baths can be detrimental to your health and your home. High humidity creates the perfect breeding ground for mold and mildew. These indoor pollutants can trigger allergies, asthma, and other respiratory problems, and eat away at sheetrock and wall studs.  

Installing a new exhaust fan—or replacing an old, inefficient one—will allow you to control the humidity level, head off damage, and remove odors from your bathroom. There are different types of bathroom fans to choose from so it’s a good idea to find the bathroom fan size and features to best fit your home. We’ve put together this guide to explain the different types of fans available and help you decide which is best for your home.