DIY Laundry Detergent 3 Ingredients: An Old-Fashioned Recipe

Our old-fashioned 3 ingredient laundry detergent takes about 20 minutes to mix and costs pennies a load. Here's the recipe, plus HE and safety notes.

There's something satisfying about mixing up your own cleaning supplies, the way our grandmothers did. When folks ask us for a DIY laundry detergent 3 ingredients recipe, this is the one we share: washing soda, borax, and a bar of grated soap. It's the simplest version we know. It takes about twenty minutes, makes enough for dozens of loads, and you know exactly what's in it.

A quick, honest note before we start: technically, this mixture is a soap-based laundry powder, not a synthetic detergent like the jug you buy at the store. That difference matters in hard water and in some machines, and we'll cover it below so you can decide whether a homemade batch is the right fit for your household.

Here's everything you need and the step-by-step for our favorite 3 ingredient laundry detergent.

Why Choose a DIY Laundry Detergent 3 Ingredients Recipe?

Folks make their own laundry powder for a few good reasons:

• Cost. The ingredients are inexpensive and a single batch stretches a long way at one or two tablespoons per load.
• Simplicity. Three ingredients, no dyes you didn't choose, and no mystery list on the back of the box.
• Less packaging. Boxes of washing soda and borax last for several batches, and you refill the same jar again and again.
• Old-fashioned charm. A pretty jar of homemade powder on a laundry shelf just looks nice, especially with a vintage scoop.

Curious how much a batch will make and what it costs per load where you live? Plug in your prices below.

Finding the Right Ingredients

Washing Soda

Washing soda is sodium carbonate. It softens water and helps lift grease and dirt. You'll usually find it in the laundry aisle near the borax. It is not the same thing as baking soda (sodium bicarbonate), which is much milder. Some people make washing soda by baking baking soda in a low oven until it changes, but buying a box is easier and more consistent.

Borax

Borax is sodium borate, a naturally occurring mineral that's been sold as a laundry booster for well over a century. It helps soften water and boosts the cleaning power of the soap. Some households prefer to leave it out; if you do, replace it with more washing soda and expect slightly different results.

Bar Soap

Choose a true soap bar without heavy moisturizers. Traditional laundry bars are made for this job and grate easily. Pure castile bars work too. Skip beauty bars with added lotions and creams, since those extra oils can leave residue on fabric. If you like a scent, pick a scented laundry bar rather than adding essential oils directly to the powder.

Using Homemade Detergent in HE Washers

High-efficiency washers use much less water, so they need a low-sudsing product. The good news is that this recipe makes very few suds. Still, a few cautions apply:

• Use less. Start with 1 tablespoon per load in an HE machine.
• Dissolve it first if you can. Stirring the powder into a cup of hot water before adding it to the drum helps prevent undissolved flakes.
• Check your manual. Some manufacturers recommend only HE-labeled commercial detergents, and using something else may matter for your warranty. It's worth a look before you switch.
• Run a cleaning cycle regularly. Soap can build up in any machine over time. A monthly hot cleaning cycle keeps things fresh.

Variations to Try

• Liquid version. Dissolve the grated soap in hot water on the stove, stir in the washing soda and borax, and dilute in a bucket. It gels as it cools; shake before each use.
• Extra stain power. Add a half cup of oxygen bleach powder to the dry mix for whites and kitchen towels.
• Borax-free. Use 2 cups washing soda and 1 bar of soap. It cleans well in soft water.
• Gentle wash. For delicates, use a castile bar and only a tablespoon of the mix.

Pair your homemade powder with our homemade fabric softener for a fully DIY laundry routine, and use the laundry detergent calculator any time you want to scale up a batch.

Safety Notes

Homemade doesn't mean harmless. Washing soda and borax are household chemicals, and they deserve the same respect you'd give any store-bought cleaner.

• Wear gloves. Washing soda is alkaline and can irritate skin. Borax can also irritate skin and eyes.
• Avoid the dust. Pour slowly, work in a ventilated spot, and consider a simple dust mask. Don't breathe in the powder.
• Keep it out of reach. Store the jar up high, away from children and pets, and never in a container that could be mistaken for food or sugar.
• Label everything. Clearly mark the jar with its contents.
• Don't ingest. If any is swallowed or gets in the eyes, follow the product label directions and contact Poison Control or a medical professional.
• Keep tools separate. Use a grater and bowl that are set aside for cleaning projects, not cooking.
• Spot test. If you have sensitive skin or special fabrics such as wool or silk, test on a small load first or stick with a product made for those fabrics.

Storing Your Batch

Keep the powder in an airtight jar or tin in a dry spot. Moisture makes it clump; if that happens, break it up with a fork. A batch keeps well for months. We like to tuck a vintage measuring scoop inside the jar, and an old canning jar makes a pretty container. If you find one at a sale, our guide on how to clean old jars will get it ready for the laundry shelf. For more old-fashioned household know-how, browse the blog.