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How to Make Your Own Laundry Detergent

person pulling laundry out of machine at laundromat
Popular Science

Warning: you might get sucked into actually liking doing laundry.

Everyone wears clothes, everybody's clothes get dirty, and even though you hate it, everyone needs to do laundry. And unless you're fortunate enough to have a washer and dryer at home, washing your clothes may be more than annoying—it can also be expensive.

If this is your situation, or you simply enjoy making things from scratch—because why not—you can try making your own laundry detergent. Just as effective with your dirty socks as whatever you buy in stores, it is not only easy to make and incredibly cheap, but can also be hypoallergenic, custom-scented, and environmentally friendly.

It's important to note that you'll need a lot of containers for the finished product. DIY laundry detergent is a go-big-or-go-home kind of deal, yielding up to 2 gallons per batch. You said you wanted some savings, right?

What you'll need


  • ½ cup borax
  • 1 bar of soap
  • ½ cup sodium carbonate
  • 2 gallons of water
  • 1 ounce of essential oils (optional)


  • Large bucket (must hold more than 2 gallons)

Preparation time

  • About 20 minutes (plus 24 hours of resting)

The soap

Most people use the classic Fels-Naptha soap, which is cheap and good with dirt: you can get a 5.5-ounce bar for as low as $0.99.

Fels-Naptha contains coconut acid, palm acid, and tallow acid, all fatty acids that act as emollients and surfactants. These two types of compounds allow water and oil to combine, attracting dirt directly from the fibers of your clothes, pulling it into the water to be rinsed away.

Originally, Fels-Naptha contained benzene, a strong dissolvant that originally gave the soap its fame back when it was introduced in the late 1800s. But benzene is a chemical compound derived from petroleum that is both carcinogenic and—you guessed it—not the best thing to have soaking into the environment. The soap was reformulated, but even though it no longer contains benzene, it still isn't entirely eco-friendly.

If you want to go with the greenest version of this recipe, you can use the same amount of pure castile soap. This type of soap has been around for centuries and is traditionally made out of vegetable oils (such as olive, palm, or coconut oil), water, and lye, and it is organic and safe. Pure castile soap is a little more expensive than Fels-Naptha, but still cheap enough to make it an excellent choice—you can find it for as little as $1.25 for a 4-ounce bar.


Borax is a water soluble salt derived from boron and one of the classic ingredients in laundry detergents, known for its powers of disinfection and whitening. It is a white, crystalized powder you can easily find in supermarkets and online for around $5. Borax cuts through grease and helps loosen soil and stains, which is why it is not only used in laundry detergent, but in other kinds of cleaners as well.

Borax is a natural compound, but it is also a cleaning agent you want to handle with caution. You don't want to inhale or ingest it, so we strongly suggest you cover your nose and mouth while using it. Still, borax is not toxic when used in low concentrations as a cleaning product.

In this case, borax concentration reaches up to only 0.5 grams per load, which is safe for you and your clothes.

Sodium carbonate

Another classic ingredient of household cleaning products, sodium carbonate is also known as washing soda or soda ash. A cousin to baking soda, sodium carbonate works as a bleach substitute and neutralizes odors. The most common branded version of this compound is Arm & Hammer Super Washing Soda, which you can find for as low as $4.12 for a 55-ounce box.

Washing soda also acts as a water softener, meaning it eliminates elements such as calcium, iron, magnesium, and other minerals that make water "hard." These elements are not only rough on your clothes, but also on your machine, since they tend to build up inside it. Eighty-five percent of people in the U.S. have hard water, so washing your clothes with detergent that contains compounds such as sodium carbonate means a longer and better life for both your pipes and your washing machine.

Make it smell good (if you want)

woman and girl smelling fresh laundry
Popular Science

There are people who buy their laundry detergent not because of its cleaning power or how environmentally friendly it is, but just because "It smells nice." If this is not you, feel free to skip this step. But if it is, this is where you can get creative. You can add up to 1 ounce of any combination of essential oils to the mix to make it smell exactly as you like.

Just keep in mind that the more essential oils you add, the stronger the scent of your detergent will be. Also, adding essential oils will make it less-suited for delicate skins, so if you're washing baby clothes or are extremely sensitive, either skip the scent or keep it to the bare minimum.

Stir things up

Grate the soap into a large pot and dissolve it in 6 cups of hot water. Put it on the stove and heat it on medium for about 10 minutes, stirring constantly until the soap completely dissolves. Don't let it get too hot—you only want to help the blending process.

You'll need 2 gallons of warm water in total, but you're not going to pour it all at once. First, fill your bucket with 13 cups of water, then pour in the melted soap and stir.

Put on some gloves and cover your mouth and nose—use a surgical mask or any kind of cotton fabric, such as a bandana—when you add the borax and sodium carbonate. This will thicken the mix, so stir well to make sure everything is blending properly.

Pour the rest of the water into the bucket four cups at a time as you continue to stir. If the mix gets too thick, you can use an immersion blender. Make sure to wash the tool thoroughly afterward so there's no risk of getting any detergent in your food.

If you want to add scent to your laundry detergent, this is your chance. Add up to 1 ounce of the essential oil(s) of your choosing and stir to blend.

Cover your bucket and let it sit for 24 hours. After that, the mixture will look like a gel with a lumpy consistency, but despair not—the soap will dissolve easily in the washing machine if you give it a little shake before using it.

If you think the detergent is too thick, you can always add more water. Just keep in mind that the less concentrated it is, the less cleaning power it will have. For large loads, just use one cup of detergent.

And finally, since you're probably not used to having a lot of detergent bottles at home at once, remember to store both the detergent and the remainder of the ingredients away from children and pets.

Written by Sandra Gutierrez G. for Popular Science and legally licensed through the Matcha publisher network. Please direct all licensing questions to legal@getmatcha.com.

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