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How to make bar soap in 3 steps.

The simplifed version.

Soapmaking from scratch.

So you want to learn how to make natural soap? Well then, you've come to the right place. Natural soapmaking has 3 necessary parts to be a success. There are some other details that we will need to cover as well, but you will always need liquid (water), lye, and oil or fat to make natural bar soap.

Natural Bar Soap & Reclaimed Wood Soap Saver

Part 1 - Lye (NaOH)

Always use proper safety when working with lye. Lye in soapmaking is a strong alkali used to create basic solutions, which is exactly what you will need to do. While creating this solution though, you should first take the proper safety precautions when working with caustic soda, aka lye (NaOH) or sodium hydroxide. There is also potassium hydroxide (KOH), but this is commanly used in the production of liquid soap.

Safety First! Always use caution and follow safe handling procedures and practices when handling lye. Sodium hydroxide will cause a chemical burn if it comes into contact with human skin and can cause blindness as well if it happens to get in your eyes, It also puts off a noxious odor when mixed with liquid that will take your breath away and burn your throat and lungs if inhaled. Lye can be REALLY nasty stuff if not respected. Follow these safety steps and you should be just fine in your soap making endeavors.

  • Wear eye protection
  • Use latex or nitrile gloves when handling
  • Always have proper ventilation to expell fumes
  • Keep distilled white vinegar on hand, this will neutralize chemical burn if lye contacts skin
  • Pour lye into liquid, not liquid into lye when making a basic solution. Pouring lye into liquid prevents splashing
  • Never use aluminum materials when working with lye (NaOH) or (KOH), the reaction produces hydrogen gas

Although this may seem intimidating, and should be respected, sodium hydroxide and potassium hydroxide are both nessecary in the production of soap. It is worth noting that sodium hydroxide (NaOH) and potassium hydroxide (KOH) are not interchangable in soap making. Typically KOH produces a softer soap and is used to make liquid soap.

Working with lye is usually what scares people away from making natural bar soap at home but if you follow the safety precautions and pay attention to what you are doing everything should be just fine and you don't need to be fearful about handling this nessecary ingredient.

Lye for soapmaking

Part 2 - Liquid (Water)

A mixture of liquid (water) and sodium hydroxide is part 2 of making bar soap. Sounds simple right? Well, it really is. The complicated part is putting together a good recipe and getting all of your meausrments correct. Not to worry though! I will explain the whole process for you! Later in this article we will discuss how to calculate soap mold volume and how to use a lye calculator to determine the quanities of each ingredient.

You may be wondering if it has to be water or can it be any liquid? Almost any liquid can be used! Does not have to be just water. If you do use water, and this is a good place to start if you are new to soapmaking, you should choose distilled or spring water. Tap water may be just fine, but also may contain elements that are not present in distilled water because distilled water is just that, distilled water. Also, if your tap water is really hard or really soft, this may affect the outcome of your bar soap. Using distilled water is the safest bet because you can expect repeated results.

Other liquids such as goats milk, coconut milk, coffee, & beer are some of the other liquids that are suitable for soapmaking. Of course do your research on how to make soap with these liquids because they all will react differently with sodium hydroxide.

When mixed with a liquid, sodium hydroxide creates an exothermic reaction which is just a fancy way of saying that it gets hot when combined with a liquid. So for example, if you were soaping with coconut milk, you may want to freeze your coconut milk before making a basic solution with lye to prevent boiling and curdling the coconut milk, YUK! Another example would be soaping with beer. You must first let the beer go flat, then boil off before adding the lye. We will do a post on soapmaking with liquids other than water in the future. For the purpose of this article, let's assume that the soapmaker will be using water or distilled water.

Part 3 - Oil or Fat

When the lye/water solution is mixed with oil or fat, it goes through a process called saponification. Which type of oil or fat you choose is up to you. Just take note that different oils and fats will have unique qualities on the final soap bar.

Yes, soapmaking is part art and part science. Let's talk about the art of soapmaking first. Oil selection is crutial in formulating a bar soap recipe. For example, organic coconut oil renders a hard bar of soap and is known for it's cleansing properties and makes lots of bubbles in the lather in the final bar of soap but using too much organic coconut oil in a recipe will cause the soap to be overly drying to the skin unless a high "superfat" is used. More on "superfatting" later.

Typically, you want to find a nice balance between the oils that you are using in your recipe. Research the qualities and benefits of different oils used in soap making. They will all have a different effect on your final bar of soap. I've used this chart from to show the qualities of different oils used in natural soapmaking.

Some other details...

Natural Handmade Soap Bars

At this point you may be wondering, "Ok, how do I know the quantity of each ingredient to use and where do I find them?

You can purchase soap making supplies at

You will also need to use a lye calculator for determining the amount of lye to be used in a batch of handmade soap.


The lye calculator will actually help you do a few things:

  • Determine the amount of lye needed in a given recipie
  • Determine the amount of oil needed in a given recipie
  • Determine the amount of liquid (water) needed in a given recipie
Lye Calculator for Handmade Soap

A quick note about "superfatting". Superfatting soap means that there will be a percentage of oil that doesn't get turned into soap. Having extra oil in the bar soap will help with moisturizing qualities. Common superfats are between 1-10% depending on the oils that you use in your soap recipie.

So once you've built your all natural soap recipie and aquired all of your ingredients it's time to make bar soap! Here is the cold process.

  • Weigh out liquid
  • Weigh out lye
  • Mix lye and liquid (always lye into liquid to prevent splashing)
  • Weigh out oils
  • Melt oils
  • Mix oils and lye
  • Bring to trace
  • Add colorants and fragrance or essential oils
  • Pour into mold

Note: "Trace" is when the batter begins to thicken and becomes 1 color. An electric stick blender works well for this and can be purchased online or at any retailer selling home goods.

Electric Stick Blender used in Natural Soap Making


Soap making requjres 3 parts to be successful.

  • Lye
  • Water
  • Oil or Fat

Build out your recipie, mix the ingredients, add some essential oils and herbs, then....MAGIC! Now you have the simpified version of how to make soap.

Also, be sure to visit the Soap Shop and check out our handmade natural soap bars and body care. All of our products are plant based formulas that have many amazing posititve benefits for your skin. Use coupon code "ZENSOAP" to save 15% at checkout.

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