You may be searching for the best air purifiers for allergies, pets, mold, wildfire smoke, or exhaust—such as from cars or industrial buildings—to protect yourself and your home from potentially harmful air pollutants, especially as the seasons change.

As winter creeps in and the outside air gets colder, having a good air purifier for your living space (especially your bedroom) is essential to reducing airborne particles. Closed windows and older heating systems often trap stale air and indoor pollutants, and microscopic allergens like pet dander and dust mites circulate your home instead of wafting outside. Plus, heating devices like fireplaces, furnaces, and heaters can create soot, dust, and other potentially harmful odors.

If you don’t want to break the bank on a large, expensive whole-house air purifier, a smaller, more portable one can still be extremely beneficial to your health. You can move it around your house and keep it in your bedroom to help keep the air healthy and germs at bay as you sleep.

These on-sale, WIRED-tested air purifiers below can help make your home healthier this winter for less. All of these picks have HEPA filtration options, which capture microscopic airborne viruses, bacteria, and respiratory droplets that increase the likelihood of illness, especially when people spend more time indoors together during the colder months. Keeping the air continually filtered and circulating also helps ease asthma triggers, congestion, and allergy flare-ups that often get worse as the temperature drops.

A Discounted Air Purifier With Heating and Cooling Capabilities

As we move toward winter and temperatures drop, this combo heater-air purifier may be the answer to your prayers. This is Blueair’s small-room model with coverage up to 175 feet, so it’s ideal for bedrooms. It stands less than 2 feet tall and includes built-in heating and a cooling fan, so it can be used year-round as temperatures rise and fall. This combo air purifier also offers an easy-to-use connected app, HEPA filtration and electrostatic technology to capture pollutants, and a built-in air quality index indicator light that lets you check air quality at a glance. It’s 55 percent off on Amazon right now, and at Shop it’s $150 off when you sign in at checkout.

A Bedroom Air Purifier for Pet Allergies

I first bought this little air purifier when I was moving into my small Brooklyn apartment with two cats and a roommate who has allergies. It can exchange air the recommended 4.8 times per hour in a 219-square-foot area, so a roughly 15×14-foot room or smaller is best for it. You can opt for the pet-specific filters for $35, which include a nylon pre-filter mesh to catch larger pet hair and fur before it reaches the deeper internal HEPA filter, three-stage filtration (including a prefilter and the main HEPA filter), and an enhanced activated carbon filter to absorb pet odors more efficiently.

An Air Purifier That Doubles as a Sunrise Alarm Clock

This is another dual-purpose air purifier that we love for bedrooms. It can clean the air in a small 140-square-foot room in 13 minutes at 4.8 air exchanges per hour, and also works as a sunrise alarm clock that gradually wakes you. It’s also got an adjustable nightlight and clock functions. If you’re like me and short on space, or have been wanting to try a sunrise alarm clock and want cleaner air, this purifier can do it all.

Other Discounted Air Purifiers We Like

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