Using the Bramble Berry Lye Calculator

I love creating and customizing my own cold process soap recipes. There is a lot of joy in experimenting and finding just the perfect combination of ingredients that make your skin feel great. Using a lye calculator is a lot easier than figuring out how much lye you need in your soap recipe the ‘old way’. Excited? Ready to get started? Yay! If you’re a new soaper, please read this important post on handling lye correctly and get the beginner’s DVD here.

Step 1: Find the oils you are going to use in your recipe
Step 2: Enter in the ounces of each oil
Step 3: Decide what superfat amount you are going to use on the drop down menu. Our calculator goes from 2% to 10%.*
Step 4: Click ‘Calculate’ button
Step 5: Presto! The ‘Lye amount’ & the ‘liquids suggested amount’ appear for you to use in ounces

* Why does the lye calculator only go down to 2%? Because there are slight variations in saponification values based on which book or expert the information comes from and because each slight variation has a range for a saponification value, to be on the extra safe side, we’ve given a 2% margin of error and will not allow the recommended lye amount to fall under the 2%.

* Why does the lye calculator only go up to 10%? When you have a superfat amount higher than 10%, there is literally 10+ percent of your soap bar that is now oil. While this makes for a moisturizing bar and a extremely luxurious bathing experience, bars made with more than 10% of superfat develope DOS (Dreaded Orange Spots) more quickly than lower superfat and (generalizing) have a lower lather and bubble size because of the excessive oil in the bar.

This is the 2nd iteration of our Lye Calculator. I hope you enjoy using it. If you have any helpful suggestions for how to improve on it, please let me know. I already have some ideas and am excited to develop them for an even better Bramble Berry experience for you.


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  1. Sara says

    Is the superfat included on the lye calculator
    Or do you have to add it in yourself. If I select a
    5% superfat… Do I have to do the math and add it
    In or does the lye calc have it already included in
    My recipe

    • says

      Hi Sara!

      The lye calculator will actually adjust everything for you! You just add in all your ingredients and choose the percentage of superfat you want, and voila, it will give the amounts you need for your recipe! :)
      -Becky with Bramble Berry

  2. Anne-Marie says

    Little Shadow,

    Great suggestions – thank you.


    Aw, shucks. That's high praise coming from you. Thank you. =)

  3. Joanna says

    Off topic but TOTALLY relevant to everything online…
    I love your new site design.

    LOVIN IT!!!!!

  4. Little Shadow Creations says

    ~Oh, one more thing…..
    Being able to change the water discount percentage would be pretty sweet too!

  5. Little Shadow Creations says

    ~You should some how incorporate a built in f.o./e.o. calculator with a drop down % menu into your lye calc., then it would be the best, most complete lye calc. on the web(in MY opinion).