Understanding SAP Values: A Complete Guide for Soap Makers

What is a SAP Value?

The Saponification Value (SAP value) is a number that tells you how much lye is needed to fully saponify (convert to soap) a given weight of oil or fat.

There are two types of SAP values you need to know:

• NaOH SAP value: Used for solid bar soap (sodium hydroxide)
• KOH SAP value: Used for liquid soap (potassium hydroxide)

How to Use SAP Values

The formula is simple: multiply the weight of your oil by its SAP value to get the amount of lye needed.

For example, if you are using 500g of Black Seed Oil (NaOH SAP = 0.1387): 500g × 0.1387 = 69.35g of sodium hydroxide needed.

SAP Values for Common Soap Making Oils

Here are the NaOH SAP values for the most common soap making oils:

• Black Seed Oil: 0.1387
• Laurel Berry Oil: 0.1360
• Sweet Almond Oil: 0.1360
• Olive Oil: 0.1340
• Coconut Oil: 0.1900
• Palm Oil: 0.1410

Using a Lye Calculator

While understanding SAP values is important, we always recommend using a lye calculator for your soap recipes. Our free Lye Calculator automatically calculates the exact lye amount for any combination of oils, including a safety discount (superfat percentage).