Hydrogen peroxide is a colorless liquid chemical. Some small amounts occur naturally, but the hydrogen peroxide you find in stores or salons is synthesized in labs.
Hydrogen peroxide* is sold in drugstores and grocery stores at a low concentration, usually at 3 to 9 percent. It can be used as a disinfectant and as bleach, including as a hair lightener. Because of this, hydrogen peroxide is an ingredient in many blonde hair dyes.
While it’s generally safe to use hydrogen peroxide* on your skin and hair, it can cause skin, lung, and eye irritation.
Hydrogen peroxide to lighten hair
Hydrogen peroxide is commonly used to lighten hair. It may be used on its own or in other blonde dyes.
Hair dye with hydrogen peroxide is considered permanent dye, which means that it will only go away as new hair grows. This is because hydrogen peroxide works in the hair cortex, the innermost part of the hair that holds the pigment that gives hair its color.
Hydrogen-peroxide-based dyes alone can help take your hair to a light blonde color. These dyes are also often used to turn dark hair a lighter color before adding another color of dye. It can turn dark brown hair red, for example.
Hydrogen peroxide and hair damage
Hydrogen peroxide is generally safe for your hair, but it can cause some issues, even in the concentrations you can buy for home use.
Although you can use hydrogen peroxide on your skin as a disinfectant, it can irritate your skin if you use too much.
When dyeing your hair with hydrogen peroxide, you might experience irritation on your scalp and around your hairline.
You can help prevent irritation by making sure your hairline is protected by petroleum jelly and clean cotton, and keeping the hydrogen peroxide in your hair for as little time as possible.
Damage to the hair cuticle
The cuticle is the outer layer of your hair. It protects and helps strengthen it.
Lightening your hair with hydrogen peroxide* can damage the cuticle, because the hydrogen peroxide needs to enter through your hair cuticle to dye the hair. Cuticle damage can lead to breakage, split ends, and frizz.
Deep conditioner treatments will help reduce damage to the hair cuticle.
Hydrogen peroxide is a type of oxidative hair dye. This means it causes a chemical reaction in the hair cortex that leads to the new hair color.
While oxidative dyes are more permanent than other dyes, this also means they cause oxidative stress for your hair. This stress ages your hair and can cause hair loss.
Breakage from damage to the hair cuticle can also lead to hair loss.
How to lighten hair with hydrogen peroxide
The safest way to lighten your hair is at a salon. However, you can safely use hydrogen peroxide* to lighten your hair at home — you just need to be careful.
Make sure you dilute the hydrogen peroxide*, protect the skin around your hairline, and go slowly to get the right color without irritating your skin.
Dyes containing hydrogen peroxide
Many permanent dyes you can buy in a drugstore include hydrogen peroxide. These dyes use hydrogen peroxide* to strip your natural hair color and make the dye last longer.
Hydrogen peroxide and baking soda
Baking soda is an alkaline, which helps hydrogen peroxide* work better in two ways.
First, it opens up the cuticle to allow the hydrogen peroxide* to get into the hair cortex more easily. Second, when mixed with hydrogen peroxide, it helps break down the melanin in hair.
To lighten your hair with hydrogen peroxide* and baking soda, mix the two ingredients into a paste, and spread it evenly throughout your hair. Leave it on for 15 minutes to an hour, depending on how dark your hair is, and then rinse it out with cold water.
Hydrogen peroxide alone
The first step to dyeing your hair with hydrogen peroxide* is to protect your skin. Cover your hairline with petroleum jelly and a cotton strip (if you have one), and wear gloves. Then you’re ready to dye.
Make a mix of half hydrogen peroxide* and half water. Put it in a spray bottle and spray a small test piece first. This is to make sure that you don’t have an allergic reaction and you’re happy with the resulting color.
Once you’re satisfied with the color, cover your neck and shoulders with a clean towel you don’t mind staining. Then saturate your hair with the hydrogen peroxide solution and leave it on for 15 minutes to an hour. Rinse your hair well.
At a salon
A trained hairstylist and colorist can use hydrogen peroxide* in a salon to lighten your hair. They’ll make sure to match the final color to your skin tone and can add highlights if necessary.
Alternative hair-lightening products
If you’re worried about the safety of hydrogen peroxide or don’t want to make your hair too blonde, there are other ways to lighten your hair. These include:
Lemon juice works best on dark blonde or light brown hair.
Combine lemon juice with water and saturate your hair with the mixture. Let your hair dry for a few hours — preferably in the sun — and then rinse it out.
Apple cider vinegar
Mix one part apple cider vinegar with six parts water and spray it all over your hair. Leave the mixture on for 15 to 20 minutes, and then rinse thoroughly. This color change might be more subtle than some of the others.
Brew a strong cup of chamomile tea and saturate your hair. This lightens your hair gradually, but should work for most hair colors. Chamomile can also brighten dull blonde hair.
Cinnamon is a great way to bring out red and blonde highlights in your hair. Just mix cinnamon powder with water to form a paste, and it spread throughout your hair. Cover your hair, leave the paste on for several hours, and then rinse.
Mix honey with warm water and spread it throughout your hair. Wrap up your hair and leave the mixture on for several hours. You can even leave the honey on as long as overnight, since it only lightens your hair slightly. Then rinse it out.
Hydrogen peroxide* and dyes containing it are a safe way to lighten your hair. However, it’s best used in a salon to minimize hair damage and ensure you get the right color.