We spent 12 hours of researching and testing to find the best window fans for bringing in cool air at night or extracting hot air out of a kitchen window. For most people, the Pelonis 9″ Twin Window Fan is a great value. But the pricier Bionaire Twin Reversible Airflow Window Fan is worth an upgrade if you need more power or less noise.
We’ve collectively researched room fans for 60 hours, and we think the lessons learned from that article apply to this category as well. Though a room fan can circulate air within a room, a window fan can bring in cool air from outside or exhaust stale air from small bedrooms or kitchens. Additionally, they’re easier to install and much cheaper—in terms of both initial cost and power consumption—than an air conditioner. They’re ideal solutions to tricky airflow situations, especially in irregularly shaped apartments or homes or when an air conditioner would be overkill.
The ultimate truth, however, is that window fans are not designed to last. They’re difficult to take apart and difficult to clean, and the small motors, which are exposed to the elements but shouldn’t get wet, can become sticky after a year or two of running. It doesn’t make sense, therefore, to spend too much on fans like this. After studying 16 models of fans (and taking cursory looks at roughly three times that number), we didn’t notice an overwhelming amount of design variation among the manufacturers. A window fan is most often built around two identical fans about 9 inches in diameter, with a small control panel centered between them. What changes between models—and what sets more-expensive models apart—are the quality and power of the fan motors, and automated or remote-controlled settings with details like built-in thermostats and IR receivers.
Great value and performance: A pick for most people
Pelonis 9″ Twin Window Fan
The Pelonis was the least expensive fan we found that also had a reversible airflow switch. That alone wasn’t enough to make it our top pick, though. It was also the least expensive fan we found where you can control each fan’s speed independently (though you can’t control their direction independently). This unit featured a built-in thermostat and generated wind force that could be felt from 20 feet away, which was similar to the output of most of the fans we tested but without much of the accompanying noise that other fans created.
Though you can align the Pelonis vertically for use in slider windows, it’s best situated horizontally within double-hung window frames. The fan measures 24 by 13 inches without the extension and 31 by 13 inches fully extended. It also has an option for a 3.5-inch plastic extender, which can maximize the fan’s width to 34.5 inches when inserted. This should be plenty for standard windows ranging between 24 and 34 inches wide.
The motors’ noise measured between 60 and 65 decibels (with a mic held directly in front of the fan), about the level of normal conversation. If you are sitting more than 10 feet away from the fan, the sound blends in mostly with the rest of a room’s ambient noise. This was roughly average for all the fans we tested, except for the similarly priced, notably louder Holmes Twin Fan, which posted a reading of 75 decibels and released an annoying high-pitched noise.
The Pelonis is backed by a one-year warranty, but we’ve found Home Depot’s return/exchange policy to be extraordinarily lenient. (At the time of writing, a two-year warranty extension can be bought for around $7 more.)
Good for larger rooms: A faster, quieter upgrade
Bionaire Twin Reversible Airflow Window Fan
If you’re willing to spend nearly twice as much as you would for the Pelonis, the Bionaire Twin Reversible Airflow Window Fan (BW2300) has everything you could possibly need in a window fan. The fan was quieter than our top pick, its wind speed could be felt from 30 feet away, 10 feet farther than our top pick. You can toggle between three settings from the unit itself or with the included remote: both fans drawing air, both fans venting air, or one fan drawing and one venting at the same time. Additionally, you can adjust the window fan to correspond with a built-in thermostat, though we think this feature is too finicky to be useful.
Bionaire makes a nearly identical model, the BWF0910AR-WCU, which we also looked at. We can’t find a discernable difference between the two except for the price (our pick, the BW2300, is usually a few dollars cheaper). If you can’t find the Bionaire BW2300 for whatever reason, the BWF0910AR-WCU is a perfectly suitable replacement.
Wirecutter editor-in-chief Jacqui Cheng has used one in Chicago for three or four years and is impressed by its power. “I bought this fan to help keep my bedroom cool in the spring/fall without having to turn on AC and that thing seriously moves a lot of air for its size,” said Jacqui. “The only finicky thing,” she added, “are the controls. It’s not entirely clear how to change the in/out flow or the speed. It’s not super intuitive; I have to basically read the buttons every single time (even though I’ve had it for years). But on the flipside, there are only a couple buttons and it’s not hard to figure out once you start pressing them.” Executive editor Ganda Suthivarakom has owned one for four months and uses both airflows regularly. “At night, when outside temps are cool here in southern California, the fan can cool down my living room in five minutes.”
The Bionaire is backed by a limited one-year warranty. (At the time of writing, a two-year warranty extension can be bought for $8.50 more.)
These picks may have been updated. To see the current recommendations, please read Sweethome’s guide to the best window fans.