Stearic Acid for Soap Making
Stearic Acid is a hard specialty oil dominated by stearic (95%). Its palmitic and stearic acids build a firm, long-lasting bar with a stable, creamy lather, making it a common backbone for cold process recipes.
Quick Facts
How Much Lye for Stearic Acid?
With a SAP value of 0.141, fully saponifying stearic acid takes 0.141 grams of sodium hydroxide per gram of oil (at 0% superfat):
| Oil amount | NaOH (0% superfat) | KOH (liquid soap) |
|---|---|---|
| 100 g | 14.1 g | 19.7 g |
| 500 g | 70.5 g | 98.5 g |
| 1000 g | 141 g | 197 g |
Real recipes use a superfat discount (typically 5%) and almost always blend several oils. Always run your full recipe through the Soaply lye calculator rather than weighing lye from a single-oil table.
Predicted Bar Properties
Derived from the fatty acid profile, for a bar made of 100% stearic acid:
Fatty Acid Profile
| Fatty acid | Percentage |
|---|---|
| Stearic | 95% |
Substitutes for Stearic Acid
The closest matches by fatty acid profile, which is what actually determines how an oil behaves in soap. Swap by weight and re-run the lye calculation, since SAP values differ:
Build a recipe with Stearic Acid
The free Soaply calculator handles the lye math, water, superfat, and property predictions for any blend of 100 oils.
Open the lye calculatorMore Specialty Oils
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