Soap Additive Calculator

Soap Additive Calculator

Salt, sodium lactate, sugar, clays — most soap additives are measured as a percentage of your oil weight. Enter your oils, pick your additives, and get exact amounts in ounces and grams.

Percentages are of OIL weight — not the total batch weight (oils + lye + water). A 2% additive in a 32 oz oil batch is 0.64 oz, regardless of how much lye and water the recipe uses.

1. Your Batch

2. Your Additives

Additive Amounts

Additive% of oilsOuncesGrams

When to add: dissolve salt, sugar, and sodium lactate in your water before adding the lye (sodium lactate can also go into cooled lye solution). Stir clays and oatmeal into a little oil or water first to avoid clumps. Salt-bar amounts (50–100%) go in at trace — and use individual molds, since salt bars set up fast and hard.