Follow our easy, step-by-step calculator to calculate the amount of lye you need for the oils in your product.
Unlike other lye calculators, the HSCG Lye Calculator shows the expected range of the saponification value (SAP Value) of each oil and the actual SAP Value being used in the calculations. This information delivers a more accurate result.
Makers love its flexibility, because you can calculate by amount or percentage, using sodium hydroxide, potassium hydroxide or both.
HSCG members also enjoy additional benefits, including setting a different SAP Value for any oil, then using it to compare calculations. Members can also save recipes for easy reference.
Disclaimer: The Handcrafted Soap & Cosmetic Guild is providing this lye calculator to soapmakers free of charge. Every effort has been made to ensure that the SAP values used herein are accurate. However, even in the best case, the SAP values provided by reputable sources are only acceptable ranges for each oil. The actual SAP value being used in the calculations is the average of the highest and the lowest acceptable level for an oil and is generally considered the norm for calculating the lye necessary for soap. However, the actual SAP value of any batch of a particular oil may be somewhat higher or lower than the value used in the calculations here (even if it falls within the acceptable range). That all being said, the HSCG is not responsible for any injuries, losses or other damages that may result from using the information provided herein.