Use a Liquid Lye Solution in Soap Making

handmade white soap
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I once had a reader from Malaysia write that she couldn't get dry/powdered lye for soap making without a "poison permit" - but that she could get a 50% lye/water solution - pre-made "liquid lye". She asked if she could use the liquid lye solution for making soap instead of making her own lye solution from scratch. Yes, you can!

Difficulty: Easy

Time Required: No extra time - just an adjustment to your procedures

Here's How:

    Make sure that your lye solution is just sodium hydroxide and water and not ​a liquid drain cleaner with other ingredients!
  2. Make sure that you know what the ratio of lye to water is. It should be stated clearly - for example, a 50% lye solution would indicate it's 50% water and 50% lye - by weight.
  3. Now, once you've established that, use a lye calculator to figure out the right amount of lye for your recipe.
  4. Now, the math of it:
    NOTE: This is based on using a 50% lye solution. If your solution is different, you'll need to adjust.
    To adjust for YOUR recipe, you'll need to start with the amount of lye called for in your recipe and figure out how much solution that will take. In a 50% solution, it's easy to figure out - just double the weight of the lye and that will give you how much solution you need. Make sure you are weighing the solution, not using liquid measure!
  5. So, if your recipe calls for 5 ounces of lye and 10 ounces of water, you would measure out 10 ounces of a 50:50 solution. (10 ounces of 50:50 solution would consist of 5 ounces of lye and 5 ounces of water.)
  1. Then, once you've got the lye properly measured/accounted for, you need to bring the amount of water up to the total called for in your recipe. With our 5 oz./10 oz. example, you just add an extra 5 oz. of water to the 50:50 solution. So, instead of 5 oz. of lye and 10 oz. of water using dry lye, you would have 10 ounces of 50:50 solution and 5 oz. of water. But since the 50:50 solution actually contains 5 oz. of lye and 5 oz. of water - it's all the same!
  2. That's it - use the diluted lye solution as you would a freshly made pitcher of lye-water to make your soap.
  3. Note: I can hear you asking now - can I pre-make my lye solution and just store it until I need it? Yes. You can, but you have to make sure to store it safely!


  1. Do NOT heat the lye liquid! I know, I know, the instructions all say to have your lye-water at about 100 degrees. However, the temperature of your lye solution is not as important as the temperature of your oils - and certainly not worth the risk of trying to heat lye-water!! If your room temperature is cold, you can use hot (NOT boiling) water as your "added water" to help bring the temperature up a bit. As long as your solution is somewhere between 80-100 degrees, you should be fine.
  2. Lye-water solution looks just like water and can cause serious burns even more quickly than dry lye! You have to be doubly even triply careful with it!! Store it away safely - as safely as you would any other dangerous chemical like acid or gasoline.
  3. Though I've repeated it above, be sure to weigh everything! Do not use liquid measures.

What You Need:

  • Lye-water solution
  • Basic oils and setup for making soap
  • Understanding of how to safely deal with lye