9 Uses for Hydrogen Peroxide

hydrogen peroxide bleach
It's well known that hydrogen peroxide can be used for hair bleaching but there are a lot of other uses as well. Blanchi Costela/Getty Images

Your bottle of hydrogen peroxide is too valuable to just stay in your first-aid kit. While the inexpensive liquid is known for its medical uses and bleaching hair, it's also a versatile substance that can be used in a host of other ways.

Hydrogen peroxide (formula H2O2) is a chemical compound that's a combination of hydrogen and water. The clear liquid acts as a mild antiseptic and comes in various potencies depending on its purpose: 3 percent (household use), 6 to 10 percent (hair bleaching), 35 percent (food-grade) and 90 percent (industrial). Most stores carry the 3 percent solution, packaged in a signature brown bottle.


For years, medical professionals recommended using hydrogen peroxide to treat minor scrapes and cuts. That's because when it's placed on the skin, it foams, which indicates it's killing bacteria. Today, doctors know hydrogen peroxide also kills healthy cells, so many no longer recommend its use for that purpose. It also can be harmful if it gets in your eyes, covers a large area of your skin or is ingested, especially the food-grade hydrogen peroxide.

But no worries. Hydrogen peroxide has many other helpful applications, some of which might be new to you. Here are nine. (The hydrogen peroxide referred to in these examples is the 3 percent version, unless noted otherwise.)


1. Remove Pit Stains

Let's face it, brownish-yellow armpit stains are embarrassing. And aggravating, especially if they develop on a fairly new garment. Erase them by creating a solution of one part dishwashing liquid and two parts hydrogen peroxide, then applying it to the stain for about an hour. Wash in cold water, then dry and wear. Note: A tough stain may also require scrubbing with baking soda.


2. Grow Mushrooms

It's crazy, but true. Hydrogen peroxide — the 35 percent version — helps combat mold infections that can ruin 'shrooms. Apply a few drops to fruiting chambers (where mushrooms grow) to instantly add oxygen.


3. Clean the Dishwasher

Use hydrogen peroxide to clean out your dishwasher. You can spray hydrogen peroxide directly into the appliance, let sit a bit, then wipe out. Or you can create a cleaning "bomb" with hydrogen peroxide, baking soda and an essential oil. Mix them and use an ice cream scoop to scoop out round balls. Let them dry overnight. To use, place the bomb at the bottom of the dishwasher. Then mix white vinegar and liquid dish-washing detergent in a glass or ceramic bowl and place in the top of the dishwasher. When you run a cycle with the bomb (along with vinegar and detergent), the peroxide will whiten and clean the appliance while the baking soda scrubs it and the oil provides a fresh scent.


4. Whiten Almost Anything, From Fingernails to Grout

Hydrogen peroxide is great at whitening and brightening many items, such as stained tiles, dirty grout and even fingernails. For the latter, combine one part hydrogen peroxide with two parts baking soda and rub the paste on your nails. Let sit for two or three minutes, then rinse away. Voilà! Gorgeous, white nails. For whitening grout, either pour the hydrogen peroxide straight on to the tile or make a paste with baking soda and scrub away.


5. Make a Mouthwash

Hydrogen peroxide is especially great for dental hygiene. Use it as a mouthwash to kill germs, making sure to dilute first (half water, half hydrogen peroxide), then swish in your mouth for one minute and spit out. Never swallow! An added benefit of this mouthwash: It'll whiten your teeth. You can also use it to disinfect and clean your toothbrush and any dental appliances, such as retainers and mouth guards.


6. Boost Your Laundry

No need to buy those expensive commercial laundry products that have the words "oxy" in them and promise to whiten your clothes. Simply add a cup of hydrogen peroxide to your washing machine when doing a load of whites. The hydrogen peroxide will also deodorize clothes and remove stains. You can pour it directly on stains but do a color-fast test first if you're applying to darker clothes.


7. Kill Mold and Mildew

As we noted earlier, hydrogen peroxide kills bacteria, but it also dispatches fungi such as mold and mildew. So grab a spray bottle of hydrogen and spray your bathroom fixtures, floors, walls, humidifier, dehumidifier, even your shower curtain. That fizzy sound will tell you it's working.


8. Grow Your Garden

Gardeners know one of the best substances for their plants is hydrogen peroxide. The all-purpose liquid can help with pest control, prevent infection on damaged trees, kill foliage fungus and combat root rot, as well as improve plant growth. That extra oxygen causes the roots to absorb more nutrients. For pest control or growth, add one teaspoon to one cup of water in a spray bottle and mist the plant. To combat root rot or fungal infections, use one tablespoon per cup of water.


9. Keep Food Fresher

Spraying salad greens with a little H2O2, then returning them to the fridge, will thwart sogginess for several days. Fruits and veggies also can be spritzed or bathed in a hydrogen peroxide solution to keep them fresher longer. Just be sure to rinse them thoroughly before eating.

Editor's note: The regular strength hydrogen peroxide (3-5 percent) is OK to ingest, but higher strengths (10 percent or more) can be toxic if swallowed. The article has been updated to clarify that.


Hydrogen Peroxide FAQ

Does hydrogen peroxide kill fungus?
Yes, using hydrogen peroxide is an effective way of getting rid of fungi, mold and mildew from floors, walls, humidifiers and tile.
Is it safe to use hydrogen peroxide as mouthwash?
Hydrogen peroxide is commonly found in mouthwash due to its germ-killing capabilities. However, if you intend to use hydrogen peroxide as a mouthwash, you'll need to dilute it with water to 50 percent beforehand. This solution will kill germs and whiten your teeth, and can also be used to clean your toothbrush and dental appliances.
What are common uses of hydrogen peroxide?
Hydrogen peroxide is commonly used for removing pit stains in shirts, whitening teeth, cleaning around the house, growing mushrooms, pest control and preserving food.
What can you clean with hydrogen peroxide?
You can use hydrogen peroxide to clean almost anything. This includes your teeth and fingernails, the dishwasher, tiles and fixtures in both your kitchen and bathroom. Many people also add it to their washing machine while doing laundry instead of expensive store-bought laundry products.
Is hydrogen peroxide safe for plants?
Hydrogen peroxide serves many purposes in the garden and is totally safe. You can use it for pest control, to prevent infection on damaged crops and kill fungi. Hydrogen peroxide is also known for improving plant growth as it provides extra oxygen for nutrient absorption.