Hard water can turn homemade detergent into a disappointing, grainy mess that leaves you wondering why you bothered. This version fixes that by whipping the finished mixture into a creamy texture that scoops easily, stores neatly, and uses just a few teaspoons per load (because laundry already asks enough of us). You get a concentrated detergent that works with the hard water formula you actually need.
A comparable commercial powder booster or detergent can cost far more per load than a homemade batch built from a bar of Fels-Naptha, washing soda, and borax.
Based on current Walmart pricing for those ingredients, this batch works out to roughly 8 to 10 cents per load, while many store-bought detergents land higher depending on brand and package size. Making your own also lets you control the texture with the optional glycerin and skip extra fragrance or additives you may not want.
You only need 3 ingredients for the base formula, or 4 if you use the optional glycerin. The finished detergent goes into a 2 quart mason jar and makes about 128 to 156 loads, depending on whether you use 2 or 3 teaspoons per load. Grab a grater, saucepan, spoon, mason jar, and either a blender or hand blender before you start.
- 🧰 Materials You'll Need
- 🔧 Tools and Equipment
- 🛠️ How to Make Hard Water Laundry Detergent
- 🎨 Customization Ideas
- 🛠️ How to Use Hard Water Laundry Detergent
- 🛡️ Safety and Care
- 📦 Storage
- 💸 Estimated Cost
- 🛍️ Need Help Finding Everything?
- ❓ Frequently Asked Questions about Hard Water Laundry Detergent
- 📌 Love this Hard Water Laundry Detergent? Pin it!
- 🖨️ Print-Friendly How-To: Hard Water Laundry Detergent
Materials You’ll Need
- 1 bar Fels-Naptha, grated fine
- 1 cup washing soda
- 1 cup borax laundry detergent
- 3 1/2 cups hot water
- 1 tablespoon glycerin, optional, for a less grainy texture
Tools and Equipment
- Grater
- Saucepan or pot
- Spoon for stirring
- 2 quart mason jar
- Blender or hand blender
How to Make Hard Water Laundry Detergent
- Grate 1 bar of Fels-Naptha finely.
- Melt the grated Fels-Naptha over low to medium heat in 3 1/2 cups hot water.
- Remove the pan from the heat and add 1 cup washing soda and 1 cup borax.
- Stir until everything is fully combined.
- If you want a less grainy texture, stir in 1 tablespoon glycerin.
- Pour the mixture into a 2 quart mason jar.
- Let it cool completely. It will separate into layers as it cools.
- Whip the cooled mixture in a blender, or use a hand blender, until it reaches a cream texture.
- Return the whipped detergent to the mason jar for storage.
Customization Ideas
- Add 1 tablespoon glycerin if you prefer a less grainy, smoother whipped texture.
- Keep the base version as written if you want the simplest, most economical batch.
- If you want to compare formulas for different water conditions, take a look at Soft or Hard Water Laundry Detergent.
How to Use Hard Water Laundry Detergent
Use 2 to 3 teaspoons per load. That gives you about 128 to 156 loads of laundry, depending on how much you use each time.
If you need another homemade option for comparison, Liquid Laundry Detergent and Laundry Pre-Treat Spray can help round out your laundry routine.
Safety and Care
Label the jar clearly and keep it out of reach of children and pets. This is a concentrated laundry product, not a food item, even if the whipped texture looks a little too much like dessert. The CDC recommends storing household cleaners and chemicals out of the reach of children and pets, and calling Poison Control right away if someone is exposed or swallows a product. You can review that guidance here: CDC cleaning and chemical safety guidance.
Avoid getting the detergent in your eyes, and wash your hands after handling the concentrate if your skin is sensitive. Use a dedicated spoon or scoop for measuring so you do not contaminate the jar with moisture.
Storage
Store the finished detergent in the same 2 quart mason jar used for mixing and whipping. Keep the lid tightly closed and store it in a cool, dry spot in the laundry area.
If the mixture settles over time, stir or whip it again to bring back the creamy texture. Keep the rim and lid clean so the jar closes well and the detergent stays easy to scoop.
Estimated Cost
Using current Walmart pricing, this batch comes to about $11.78 without the optional glycerin, or about $12.14 with it, based on the portion of each consumable ingredient used rather than the full package price. That works out to roughly 8 to 10 cents per load, depending on whether you use 2 or 3 teaspoons per wash. Prices vary by seller, size, and location.
🛍️ Need Help Finding Everything?
- Fels-Naptha laundry bar at Walmart
- ARM & HAMMER Super Washing Soda at Walmart
- 20 Mule Team Borax at Walmart
- Glycerin at Walmart
- More homemade laundry detergent and stain remover ideas
Frequently Asked Questions about Hard Water Laundry Detergent
Yes. The glycerin is optional and only helps create a less grainy texture. The base formula still uses the same Fels-Naptha, washing soda, and borax mixture without it.
That layered look is expected. Let it cool, then whip it in a blender or with a hand blender until it turns into a cream texture.
Use 2 to 3 teaspoons per load. At that rate, one batch handles about 128 to 156 loads.
No. You can whip it in a blender or use a hand blender. Either one works as long as you whip the cooled mixture until it becomes creamy.
Store it in a 2 quart mason jar with a tight-fitting lid. Keep it in a cool, dry place and use a dry spoon or scoop so extra moisture does not get into the jar.
Give it a good stir or whip it again. This detergent can settle after storage, but you can bring the cream texture back without changing the formula.
You can, but make sure you have a large enough pot for melting and mixing, plus enough storage jars for the finished detergent. Keep the same ingredient ratios and the same sequence of steps.
No. This formula is written as a laundry detergent for hard water. Keep it labeled for laundry use so nobody mistakes it for another household cleaner.
Yes, grate it finely so it melts more evenly in the hot water over low to medium heat. Bigger chunks take longer and make the mixture fussier than it needs to be.
This version is specifically the hard water formula, and it is finished by whipping it into a cream texture after cooling. That texture makes it easy to scoop in small amounts for each load.
📌 Love this Hard Water Laundry Detergent? Pin it!
Did you try this project? Tell us whether you kept the basic version or added the glycerin for a smoother texture.
🖨️ Print-Friendly How-To: Hard Water Laundry Detergent
Hard Water Laundry Detergent
Equipment
Materials
- 1 bar Fels-Naptha grated fine
- 1 cup washing soda
- 1 cup borax laundry detergent
- 3 ½ cups hot water
- 1 tablespoon glycerin optional
Instructions
- Grate 1 bar of Fels-Naptha finely.
- Melt the grated Fels-Naptha over low to medium heat in 3 1/2 cups hot water.
- Remove the pan from the heat and add 1 cup washing soda and 1 cup borax.
- Stir until everything is fully combined.
- If you want a less grainy texture, stir in 1 tablespoon glycerin.
- Pour the mixture into a 2 quart mason jar.
- Let it cool completely. It will separate into layers as it cools.
- Whip the cooled mixture in a blender, or use a hand blender, until it reaches a cream texture.
- Return the whipped detergent to the mason jar for storage.
- Use 2 to 3 teaspoons per load.
- Estimated cost is based on current Walmart pricing for consumable materials only and does not include reusable tools.
- Optional glycerin was not included in the estimated cost total because the base formula works without it.
- Label the jar clearly and keep it out of reach of children and pets.
- Avoid contact with eyes and use a dry scoop to keep moisture out of the jar.
I really prefer using the glycerin for the texture and softness but I wanted to mention that once you pour the soap into the jars you need to add a bit more water midway up or so of the jar, just to the rounded part of each jar. It makes the soap come out smoother and fills the jars better.
i used zote and it ended much firmer than mayo, more stiff than crisco in the can. i like the smell of zote better and am not a first time maker of homemade detergent. anyway.
my he washer doesn’t use much water, so took one of the jars and tried to dilute by another quart of hot water. is a little seperated after really shaking it to mix. wanted to have it mixed into laundry easier, not so thick.
am i going to have to re blend this! i could pour into a bucket and re blend and put back into my gallon vinegar jug? i mixed it with hot water!
that way i could use 1/3 cup that was thinner . Will hopefully be sent a reply!
the whipped formula did not mix well in my he machine e. i will go back to the original formula. the detergent works well but extra borax is needed for the ‘hubs’ nasty socks sometimes.
i hope i do this right lol :0)
this on my to-do list. where do most people find the fels naptha bars and the washing soda? i have friends that like that recipe, lost mine in a computer crash.
I found mine in the laundry aisle at Walmart. They’re like 3 bucks a piece.
Is it safe to use my kitchen mixer or processor with this recipe and still use the same mixer to prepare food(after its washed of course)
Thank you for the detergent recipe. I look forward to making it and saving money!