“Making Your Own Bar of Lye Soap From Scratch”

“Making Your Own Bar of Lye Soap From Scratch”

Making Your Own Bar of Lye Soap From Scratch


Making your own soap from scratch using lye can be a fun and rewarding hobby. With just a few simple ingredients and some basic equipment, you can create beautiful handmade soap bars with your own custom scents and ingredients.

In this article, I will walk you through the entire process of making lye soap from start to finish. I’ll cover the supplies you need, safety precautions for working with lye, how to calculate the correct amounts of ingredients, and detailed instructions for preparing the soap batter and pouring it into molds.

By the end of this guide, you’ll have all the knowledge you need to make your first batch of lye soap completely from scratch. The satisfaction of holding a bar of soap you created with your own two hands is so worth the effort!

What You’ll Need

Making soap from scratch requires some basic supplies and ingredients. Here’s an overview of what you’ll need:


  • A digital scale for carefully weighing out the lye and other ingredients. Accuracy is important when working with lye.
  • A stainless steel pot for mixing the lye and water solution (don’t use aluminum).
  • A thermometer to monitor temperatures.
  • Silicone molds or a wooden mold for shaping the bars of soap.
  • A stick blender to mix the soap batter to trace.
  • Gloves, goggles, and an apron for safety when handling lye.


  • Lye – Also called sodium hydroxide. This is the active ingredient that initiates the saponification process.
  • Distilled water – For mixing with the lye to create the lye solution.
  • Oils & fats – Such as olive, coconut, palm, shea butter. The fatty acids in these oils react with the lye solution to form soap.
  • Essential oils or fragrances (optional) – For scent.

Safely Working with Lye

When making soap from scratch, the lye is the most hazardous ingredient. Sodium hydroxide is extremely alkaline and corrosive, so you must take proper safety precautions:

  • Always wear gloves and goggles when handling lye crystals or lye solution.
  • Work in a well-ventilated area. Avoid breathing in lye dust.
  • Only use stainless steel, plastic, or glass containers for the lye solution. Never use aluminum.
  • Add the lye to the water slowly and stir gently to dissolve. Never add water to solid lye crystals.
  • Allow the lye water to cool before adding to oils. Hot lye can cause oils to overheat.

If you splash lye solution on your skin, rinse immediately with running water for several minutes. If irritation persists, seek medical help.

With careful handling, lye can be used safely to make wonderful handcrafted soap. Just be sure to follow all safety precautions when working with this caustic substance.

Calculating the Recipe

The first step in making lye soap is calculating the exact amounts of lye, water, and oils needed for your particular recipe.

There are various methods for developing soap recipes, but a common approach is:

  • Choose your oils – Select 2-4 oils from categories like olive oil, coconut oil, palm oil, etc. Popular combinations are olive/coconut/palm or olive/coconut/castor.

  • Determine your oil weights – Decide how much of each oil to use. A good starting point is 40% olive oil with 20% each of coconut and palm oil.

  • Calculate your lye and water – Use a lye calculator to determine how much sodium hydroxide and distilled water you need based on your oil weights.

  • Balance with superfat – Add a 5-10% superfat to leave a bit of unsaponified oils for skin moisturizing. Reduce lye to account for this.

Don’t worry – there are many easy lye calculators available online that do all the math for you once you plug in your oil amounts!

Making the Soap

Once you have your recipe figured out, it’s time to start making soap! Here is an overview of the process:

Make the Lye Solution

  • Weigh out distilled water in a plastic pitcher. Then slowly sprinkle lye crystals into the water while stirring with a plastic or silicone spoon.

  • Stir gently until all of the lye fully dissolves. Allow to cool to 100-110°F.

Melt and Combine Oils

  • In your stainless steel pot, melt your solid oils and butters on low heat. Add liquid oils once melted.

  • Allow the oils to cool to 100-110°F, ideally matching the temp of your lye solution.

Add Lye to Oils and Mix

  • With your stick blender ready, slowly pour the lye solution into the oils.

  • Start blending to emulsify, scraping the sides as needed.

  • Blend until light trace is achieved – the batter holds a bit of a “trace” on the surface when drizzled. This can take 2-5 minutes.

Add Fragrance and Coloring

  • Once trace is achieved, you can stir in any essential oils, fragrance oils, or colorants if desired.

Pour into Molds

  • Finally, carefully pour your traced soap batter into your silicone molds or wooden mold.

  • Tap the molds on the counter to release any air bubbles.

  • Allow soap to set up in the mold 24-48 hours before removing to cure.

And that’s it – you now have freshly handmade soap from scratch!

Curing the Soap

Once poured and set up in the molds, your soap bars still need 4-6 weeks of curing time before use. Here’s what happens during the curing process:

  • Saponification completes – Any remaining lye and oils finish reacting.

  • Excess moisture evaporates – Bars harden and become milder for skin.

  • ** pH decreases** – The high pH of fresh soap lowers over time.

  • Flavor and scent improve – Top notes mellow while the heart of the fragrance emerges.

Curing ensures your soap is safe and ready for the best quality lather and skin feel. Patience pays off for soap worth waiting for!

Enjoy Your Handcrafted Creation!

Now that you know all the steps and processes, it’s time to try your hand at making your own batch of soap from lye and oils!

Follow each step carefully, especially the lye safety precautions. Once you’ve mastered the basics, you can start experimenting with your own oil blends, scents, colors, and design elements.

The satisfaction you’ll feel washing up with your own handcrafted lye soap creation will make all the effort worthwhile. Nothing beats soap made from scratch!