How to clean a humidifier, according to experts. (Hint: You’re probably not cleaning it often enough.)

Sniffles? Chapped lips from the dry winter air? A humidifier can be a lifesaver, helping you breathe easier at night while keeping your home from feeling like an arid wasteland. But whether you use one only when you're sick or you keep it running all season long, knowing how to clean a humidifier is essential for your health and your machine's lifespan.

"A dirty humidifier can breed mold, mildew and bacteria. Because the device emits mist into the air, there's a risk of inhaling those contaminants, which can aggravate allergies, asthma or other respiratory conditions," says Marla Mock, president of Molly Maid, a Neighborly Company cleaning service. Minerals in your water can also lead to buildup inside the machine, which Mock says "decreases efficiency and provides surfaces for germs to cling to." In other words, skipping regular cleanings may be bad news for your health — and your humidifier.

The good news? Cleaning doesn't have to be a multi-hour chore. With a little consistency, the process is relatively quick and simple. As someone who has purchased (and ditched) more humidifiers than I care to admit while searching for "the one" (you know, a humidifier that's actually easy to maintain), I decided I'm tired of the game. This time I turned to the experts (five of them to be exact, from medical pros to cleaning specialists) to get their tips and insights on how best to care for these machines. Here’s what they said.

Table of contents

Why is it important to clean your humidifier?

"Humidifiers can make indoor air more comfortable by easing dry skin, throat irritation and breathing discomfort. If they are not used properly, however, they may worsen respiratory health by spreading bacteria or mold," says Muge Akpinar-Elci, MD, MPH, pulmonologist and dean of the School of Public Health at the University of Nevada, Reno. Akpinar-Elci adds that this can be particularly dangerous for people with respiratory issues: "For people with asthma, allergies or other breathing concerns, that can make symptoms worse and even lead to infection." These microorganisms can also pose particular health concerns for very young kids, especially babies, whose respiratory systems are still developing.

But health isn't the only reason to stay on top of cleaning. Your humidifier will thank you too. Mineral buildup — aka that white crust you might spot inside your humidifier — can tank the life of your device, clogging parts of your machine and even damaging heating elements in warm-mist models.

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How often should you clean your humidifier?

"Stagnant water is a perfect breeding ground for bacteria and mold," says Dr. Raj Dasgupta, a quadruple-board-certified doctor in pulmonary, sleep, internal and critical care medicine and chief medical adviser at Sleepopolis. Because of this, he says one of the best ways to keep yourself and your device safe is to change the water daily. "You should give your humidifier a quick rinse and refill with fresh water every day, and aim for a deeper clean at least once a week," he says.

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What you'll need

Like any project, cleaning your humidifier is a lot easier when you have the right tools on hand. Here's what you'll need:

• White vinegar (or another weak acid, like citric acid powder)

• Scrubbing brush for the tank and larger surfaces

• Small brush for the nooks and crannies

• Optional: Hydrogen peroxide (or bleach) for deeper cleans

"White vinegar is a go-to for dissolving mineral buildup, and hydrogen peroxide can help kill bacteria. A small, soft-bristled brush or even an old toothbrush is great for scrubbing out tight corners," says Dasgupta.

Unless your kitchen drying rack is constantly free (mine never is), it's worth keeping a separate drying rack or mat in your bathroom — or wherever you plan on cleaning your humidifier. I like using an absorbent microfiber drying pad because it's easy to store, soaks up water quickly and can be tossed in the washing machine when it needs a refresh.

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How to clean your humidifier with vinegar

When it comes to cleaning your humidifier, always start by checking the manufacturer's instructions — some models call for specific products or routines. That said, here are the top tips from Mock and Akpinar-Elci for keeping yours in good shape:

Step 1: Unplug your humidifier and drain any remaining water.

Step 2: Take all the removable components apart and give them a quick rinse. Distilled water is preferred, but tap water works too.

Step 3: Fill the base and the tank with vinegar for 20 minutes to loosen mineral buildup. If there are additional, smaller components, simply submerge them either in the tank or in a bowl of vinegar. Empty out the vinegar and scrub the components clean.

Step 4: Rinse thoroughly to remove all the vinegar.

Step 5 (optional): If your humidifier hasn't been cleaned in a while, or you notice signs of mold or bacterial growth, disinfect the machine using diluted bleach or hydrogen peroxide — just make sure the tank is completely free of vinegar first. Make a diluted bleach solution using 1 teaspoon of bleach per 1 gallon of water. Or, if using hydrogen peroxide, mix equal parts hydrogen peroxide and water. Fill the tank (and any other removable parts that contact water) with your chosen solution for 20 minutes. Empty the solution, then rinse all parts with hot water until you no longer smell bleach or hydrogen peroxide.

Step 5: Dry all of the parts thoroughly and keep them aired out until ready to reassemble and use.

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Pro tips for keeping your humidifier clean longer

There's no getting around it: If you own a humidifier, regular cleaning is a must. The good news? With a few simple habits, you can cut down on mineral buildup and bacterial growth — making your machine easier to maintain while saving yourself some scrubbing later. Here's what our experts recommend:

• Refill daily: Dasgupta recommends always using fresh, clean water to prevent bacteria and mold growth.

• Empty the tank when not in use: "Avoid leaving standing water in the tank for days at a time. That's when bacteria and mold really take hold," Dasgupta says.

• Use distilled water: While you can use tap water, Dasgupta notes there are benefits to using distilled water. "Using distilled water instead of tap can reduce mineral buildup that feeds microbial growth."

• Dilute stronger cleaning solutions: Mock stresses that it's important to properly mix bleach or hydrogen peroxide when cleaning, as "straight bleach or harsh cleaners can damage the unit or leave harmful residues."

• Dry thoroughly before storing: Akpinar-Elci recommends making sure you dry your humidifier completely before storing it to ensure you're not leaving behind a breeding ground for minerals or microbes.

• Replace the filter regularly: As with your AC or home air purifier, it's important to regularly replace your humidifier's filter. While it may vary by manufacturer, a good rule of thumb is to swap it out every one to two months.

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Easiest humidifiers to clean

As I mentioned, I've tested plenty of humidifiers, but these two are by far the easiest to keep clean.

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FAQs

What is that pink or orange residue in my humidifier?

"Pink or orange slime is often mold or a bacteria such as Serratia marcescens, which loves damp environments," says Dasgupta. To prevent buildup, Dasgupta recommends using "distilled water and cleaning the tank regularly with vinegar and a brush." Following the vinegar, soaking with an antimicrobial cleaner, like a bleach or hydrogen peroxide solution, can also help prevent buildup.

Can you use dish soap to clean a humidifier?

Because soap won't kill off microbes or take care of mineral deposits, Mock doesn't recommend using it to clean your humidifier. However, Dasgupta says that it may be helpful between deep cleans. "Mild dish soap is fine for general cleaning, especially if you rinse thoroughly to remove any residue. Soap won't tackle mineral deposits as well as vinegar, but it's a safe and easy way to keep the tank clean in between deeper cleans," he says.

Can you use tap water in a humidifier?

Yes, though distilled water is best. "Room temperature or cool water is best for most humidifiers, and distilled water is strongly recommended. Tap water can contain minerals that create buildup inside the machine and release white dust into the air, while distilled water keeps the device cleaner and the air healthier," says Dasgupta.

What is the healthiest humidity level for a home?

According to David Edwards, PhD, biophysicist and founder of Sensory Cloud, the optimal humidity level for your health is 40% to 60%. He says that when air is dry, which he defines as less than 40% relative humidity, "our upper airways lose so much water to humidify inhaled air that they [can] become inflamed." He adds, "Dry airways also generate a lot of mucus, which is why we often get a plugged nose when we are outside in very cold weather." On the opposite end of the spectrum, too much humidity can also pose health risks. "When relative humidity is as high as 70% or greater, the risk of fomites in the air goes up," he says.

For people with mold or dust mite allergies, board-certified allergist and immunologist Dr. Meagan W. Shepherd recommends keeping humidity levels between 30% and 50% to further reduce the risk of "proliferating mold and dust mite allergens in the home."

Are humidifiers safe to use?

According to the United States Environmental Protection Agency (EPA), humidifiers are safe for most healthy individuals, as long as they're used correctly and kept clean. To reduce the risk of burns from boiling water or hot steam, especially if you have young children or shaky hands, Akpinar-Elci recommends using a cool-mist humidifier rather than a warm-mist option. Shepherd also cautions against humidifiers for patients with allergies, since these appliances have a risk of encouraging dust mite and mold growth if they create too moist an environment. Ultimately, if you have allergies or a respiratory condition, it's best to talk with your doctor or other health care professional before using a humidifier.

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Meet our experts

• Marla Mock, president of Molly Maid

• Muge Akpinar-Elci, MD, MPH, pulmonologist and dean of the School of Public Health at the University of Nevada

• Raj Dasgupta, MD, quadruple-board-certified in pulmonary, sleep, internal and critical care medicine and chief medical adviser at Sleepopolis

• David Edwards, PhD, biophysicist and founder of Sensory Cloud

• Meagan W. Shepherd, MD, board-certified allergist and immunologist, founder of the Allergy Aesthetic

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Our health content is for informational purposes only and is not intended as professional medical advice. Consult a medical professional on questions about your health.