How to Clean a Humidifier with Hydrogen Peroxide in 2023

This is our guide on how to clean a humidifier with hydrogen peroxide. 

Cleaning a humidifier regularly is essential if you want it to perform well. Regular maintenance also ensures that the humidifier can last you a long time. 

To that end, a humidifier needs regular cleaning, daily replacement of water, and periodic replacement of the filter. You may even have to empty the tank out between uses. 

If you don’t keep up with the maintenance and cleaning of the unit, it could have adverse effects on your health as well. 

Hydrogen peroxide is really useful for cleaning a humidifier, as it prevents mold, and also deals with any microbes. 

Keep reading as we give you a step-by-step guide on how to clean a humidifier using hydrogen peroxide and also answer all of your humidifier cleaning questions. 

Is It Safe To Clean A Humidifier With Hydrogen Peroxide?

First things first, is it even safe to clean a humidifier using hydrogen peroxide? 

If it comes in contact with your skin, hydrogen peroxide can cause irritation, burns, and even blisters. Furthermore, the fumes from hydrogen peroxide can be toxic if inhaled in high volume. However, it is perfectly safe to use hydrogen peroxide to disinfect your humidifier’s water tank. 

In fact, the mixture we recommend using is 3% hydrogen peroxide that has been heavily diluted with water. This makes a weaker solution that is less abrasive than just the hydrogen peroxide, but still strong enough to agitate any contaminants. 

That said, it is important to use proper protective gear while handling and working with hydrogen peroxide, as you’ll see below. 

Why Use Hydrogen Peroxide To Clean A Humidifier 

Hydrogen peroxide is a great disinfectant and perfectly safe to use for cleaning a humidifier. It effectively kills most germs, bacteria, and other disease-causing microbes that may have accumulated in your humidifier’s water tank.

Another massive benefit of using hydrogen peroxide to clean a humidifier is that the abrasive composition helps agitate any stubborn stains, mineral deposits and the like in your humidifier. 

And if you notice mold developing in your humidifier’s water tank, cleaning it with hydrogen peroxide is the easiest and most effective solution. 

What You’ll Need To Clean A Humidifier With Hydrogen Peroxide

So now that we’ve established that hydrogen peroxide is safe to use for cleaning a humidifier, let’s get into what you’ll need to do it. 

Humidifier Cleaning Cheat Sheet

Here’s all the stuff you’ll need to clean your humidifier: 

– Distilled water

– 3% hydrogen peroxide

– Rubber gloves

– A face mask

– Goggles or other eye protection

– Dish soap

– A sponge

– A stiff bristle brush

If you’ve got all that stuff sorted, it’s time to get cleaning! 

How To Clean A Humidifier With Hydrogen Peroxide

Step 1: Prepare The Cleaning Solution

The first thing you need to do is prepare the cleaning solution. Start by adding 3 parts distilled water and 1 part hydrogen peroxide to a container. Allow it to mix thoroughly and set it aside. Here, we urge you to wear rubber gloves, goggles, and a face mask while handling the hydrogen peroxide. 

Using distilled water is essential, as it is completely free of any contaminants, minerals, or heavy metals, all of which could deposit in your humidifier’s water tank and cause mold to develop. 

If any chemicals come in contact with your skin, rinse them off immediately with clean water. If you feel excessive irritation or burning, contact a physician. 

Step 2: Pour The Solution Into The Water Tank 

Next, pour the cleaning solution into the humidifier’s water tank and shake it vigorously. After that, let it sit for at least an hour. Shaking allows the cleaning solution to cover the entire surface of the tank. 

Similarly, by letting the cleaning solution sit for a while, you allow it to work more effectively and kill any bacteria in the tank. 

Another benefit of letting the solution sit for a while is that if the water tank has developed mold, the hydrogen peroxide has a chance to work more efficiently and remove it all. 

It is also essential that you clean parts other than the water tank that may have been exposed to mold or contaminants. 

Step 3: Empty The Tank And Clean It With Dish Soap

After it’s been sitting for about an hour, pour out the cleaning solution and go over the whole tank with the dish soap and sponge. 

You don’t necessarily need to do this step as the tank is already clean, but it’s worth it if you’re as much of a germaphobe as we are! Getting up close and personal with the sponge also lets you look for any spots that you may have missed, any remaining mold, or any stubborn stains that just won’t budge. 

If you see any of those things, you might have to go over them with the bristle brush. 

What Happens If You Don’t Clean Your Humidifier

Cleaning a humidifier regularly is the best way to keep it performing optimally. Regular cleaning also ensures a longer lifespan for your unit and better humidification throughout that lifespan. If you don’t keep up with the maintenance, there are a number of problems that you could have to deal with. 

Poor/Slow Humidification

One problem common with humidifiers that don’t get cleaned regularly is poor humidification. These units are slow to get going and don’t work nearly as well as those that have been maintained regularly. 

This usually happens due to mineral build up in the tank, nozzle, or filter, which can even result in mold! And that brings us to the next big problem. 


The biggest issue with humidifiers that don’t get cleaned regularly is the risk of developing mold. The chances of a water tank or filter developing mold increase further if you are using mineral-rich water in your humidifier. 

Not only does mold cause your humidifier’s performance to suffer, but it could even be a major health risk! If that mold is released into the air, it can cause coughing, respiratory problems, watery eyes, headaches, and even more serious medical conditions. 

How Often Should You Clean Your Humidifier?

There are many schools of thought on this topic. Some people prefer to clean the humidifier every day, while others only do so maybe once a month. 

The fact is that you don’t actually need to clean the humidifier more than once a week. Granted, that’s if the humidifier is being used normally. If you tend to leave the humidifier running for longer, like when sleeping, more frequent cleaning may be required. 

The best way to determine how often you should clean your humidifier is to refer to the manual and see what the manufacturer recommends. And then, you can adjust the cleaning interval based on your own usage. 

Additionally, if you only use the humidifier every now and again, it is recommended that you empty out the water tank between uses. In fact, most experts agree that you should replace the water in your tank every day. 


Shawn Willis is all about humidifiers. After working for some of the biggest names in the industry, he started HumidifierGuys with Scott Dawson. Now, the dynamic duo helps others figure out what they need in their next humidifier.

Shawn is an avid sports fan, motorcycle enthusiast, and has two dogs named Whiskey and Boba.