How To Make Homemade Laundry Detergent With Two Ingredients Only

Laundry is a constant in every household, but the cost of commercial detergents—and their environmental impact—adds up over time. Many store-bought options contain synthetic fragrances, dyes, and preservatives that can irritate sensitive skin or harm aquatic ecosystems. A growing number of people are turning to DIY alternatives, not out of trendiness, but necessity: simplicity, safety, and savings.

One of the most compelling solutions is a homemade laundry detergent made with only two ingredients. Yes, just two. This minimalist formula has gained popularity for its effectiveness, low cost, and ease of preparation. It’s especially favored by those with allergies, chemical sensitivities, or a desire to reduce plastic waste. What’s more, it requires no special equipment, exotic components, or complicated steps.

This guide walks through exactly how to create a powerful, natural laundry detergent using only washing soda and soap flakes—two inexpensive, widely available ingredients. You’ll learn why this combination works, how to use it properly, and how to avoid common pitfalls that could leave clothes less than fresh.

The Science Behind Two-Ingredient Detergent

At first glance, a detergent made from just two ingredients might seem too simple to be effective. But cleaning isn’t always about complexity—it’s about chemistry. The power of this recipe lies in the synergy between its components: washing soda (sodium carbonate) and grated soap (typically castile or Fels-Naptha).

Washing soda is an alkaline salt that raises the pH of water, helping it break down grease, oils, and organic stains. It softens hard water by binding to calcium and magnesium ions, which would otherwise interfere with soap performance. Unlike baking soda (sodium bicarbonate), washing soda is more potent and specifically designed for heavy-duty cleaning.

Soap flakes, usually derived from tallow or plant-based oils like olive oil (as in castile soap), act as surfactants. They lower the surface tension of water, allowing it to penetrate fabric fibers and lift away dirt. When combined with washing soda, the soap becomes more efficient, requiring less volume per load while still delivering clean results.

Tip: Always use 100% pure soap without added moisturizers, fragrances, or conditioners, as these can leave residues on clothing.

“Simple formulations often outperform complex ones when they’re based on sound chemistry. Washing soda and pure soap have been used for generations because they work.” — Dr. Lydia Chen, Environmental Chemist and Sustainable Cleaning Researcher

Step-by-Step Guide to Making Your Detergent

Creating your own two-ingredient laundry detergent takes less than 15 minutes and yields enough for dozens of loads. Here's how to do it safely and effectively.

1. Gather your supplies: You’ll need 1 cup of washing soda and 1 cup of finely grated bar soap. Choose a soap known for stain-fighting ability—Fels-Naptha is popular for its deodorizing properties, while unscented castile soap is ideal for sensitive skin.
2. Grate the soap: Use a box grater or food processor to shred the bar into fine flakes. The finer the pieces, the faster they’ll dissolve in water. Avoid large chunks, which may not fully melt during the wash cycle.
3. Mix the ingredients: In a large bowl, combine equal parts washing soda and soap flakes. Stir thoroughly until uniformly blended. Use a whisk or spoon to break up any clumps.
4. Store in an airtight container: Transfer the mixture to a glass jar or plastic tub with a tight-fitting lid. Keep it in a dry place to prevent moisture absorption, which can cause caking.
5. Label clearly: Mark the container with contents and date. This helps track freshness and prevents accidental misuse.

To use, add 1–2 tablespoons per regular load. For heavily soiled clothes or hard water, increase to 2–3 tablespoons. In high-efficiency (HE) machines, stick to 1 tablespoon to avoid excess suds.

Do’s and Don’ts of Homemade Detergent Use

While this detergent is highly effective, improper use can lead to residue buildup, dingy whites, or machine issues. Follow these guidelines to get the best results.

Do’s	Don’ts
Use warm or hot water for better dissolution of soap flakes	Don’t use cold water exclusively without pre-dissolving the mix
Pre-treat stains with a paste of detergent and water	Don’t overload the washer—this reduces cleaning efficiency
Add white vinegar to the rinse cycle as a natural fabric softener	Don’t mix with bleach—soap can react poorly with chlorine
Stir powder into water before adding clothes if possible	Don’t store near steam or humidity; it clumps easily
Shake or stir the container before each use to redistribute ingredients	Don’t expect heavy fragrance—this detergent is scent-free unless you add essential oils

Tip: If you notice film on clothes, run an empty hot cycle with a quart of vinegar monthly to clean your machine and remove buildup.

Real Example: How One Family Reduced Costs and Waste

The Rivera family of four lives in suburban Colorado, where hard water has long been a challenge for laundry. They were spending nearly $30 a month on name-brand detergents and fabric softeners, plus replacements for towels that grew stiff and gray over time.

After learning about two-ingredient detergent online, Maria Rivera decided to try making her own. She bought a 5-pound box of Arm & Hammer Super Washing Soda ($6.99) and two bars of Zote pink soap ($1.50 each)—a mild, widely available option. She grated the soap, mixed it with washing soda in equal parts, and stored it in a recycled coffee tin.

Within three weeks, she noticed towels felt softer, whites looked brighter, and there was no more musty smell in the laundry room. Her son, who has eczema, stopped having nighttime itching episodes linked to detergent sensitivity. Best of all, the batch lasted nearly five months. At under $0.02 per load, the savings exceeded $300 annually—not counting reduced dryer time due to softer fabrics.

“I was skeptical at first,” Maria said. “But now I can’t imagine going back. It’s cheaper, gentler, and I know exactly what’s touching my family’s skin.”

Customization and Troubleshooting Tips

While the basic formula works well for most, minor adjustments can improve performance depending on your water type, machine, or preferences.

• For soft water: Reduce soap slightly—too much can cause oversudsing.
• For cold-water washing: Dissolve 1 tablespoon of detergent in a cup of hot tap water before pouring into the drum.
• To add scent: Mix in 10–15 drops of essential oil (like lavender, tea tree, or lemon) per cup of detergent. Shake well and let sit overnight before use.
• For extra stain fighting: Add ½ cup of oxygen bleach (sodium percarbonate) to the mix, though this technically makes it a three-ingredient formula.
• If residue appears: Switch to liquid form by simmering 2 cups of grated soap in 4 cups of water until dissolved, then mixing with 2 cups of washing soda and cooling into a gel.

Some users report that castile soap alone doesn’t cut through oily stains as well as tallow-based soaps. In such cases, Fels-Naptha or Zote may be preferable despite being less “natural” than plant-based options.

Checklist: Getting Started with Two-Ingredient Detergent

✅ Your Quick Start Checklist:

• Buy one bar of pure soap (no additives)
• Purchase a box of washing soda (not baking soda)
• Grate the soap finely using a hand grater or food processor
• Mix equal parts soap and washing soda in a dry bowl
• Store in a labeled, airtight container away from moisture
• Start with 1 tbsp per load and adjust as needed
• Add white vinegar to the rinse cycle for softness and odor removal
• Clean your washing machine monthly with vinegar to prevent buildup

Frequently Asked Questions

Can I use baking soda instead of washing soda?

No. Baking soda (sodium bicarbonate) is milder and does not have the same water-softening or grease-cutting power as washing soda (sodium carbonate). Substituting it will result in significantly weaker cleaning performance, especially in hard water areas.

Is this detergent safe for HE machines?

Yes, but use sparingly—only 1 tablespoon per load. Because the formula produces minimal suds when used correctly, it’s compatible with high-efficiency washers. Just ensure the soap is finely grated and preferably pre-dissolved in hot water if your machine struggles with powder dispersion.

Does it disinfect clothes?

Not inherently. This detergent cleans but does not sanitize. If you need disinfection—for example, after illness or for cloth diapers—add a color-safe oxygen bleach to the wash cycle or wash in water hotter than 140°F (60°C). Tea tree oil can offer mild antimicrobial benefits if added to the mix.

Final Thoughts and Call to Action

Homemade laundry detergent made with just two ingredients proves that simplicity can be powerful. By combining washing soda and pure soap flakes, you create a cleaner that’s effective, economical, and transparent in composition. There’s no mystery chemistry, no greenwashing, and no recurring subscription fees.

Thousands of households have already made the switch—not because it’s trendy, but because it works. Whether you're motivated by health concerns, environmental responsibility, or budget constraints, this solution offers real value without compromise.

You don’t need special skills or equipment to begin. With less than $10 and a few minutes of effort, you can make enough detergent to last months. Try it for your next few loads. Observe how your clothes feel, how your machine performs, and how much you save.

💬 Have you tried making your own detergent? Share your experience, tips, or questions in the comments below—your insight could help others make the switch too.