Can I use volume measurements?

No! You must always weigh all ingredients (oils, water, and lye) using an accurate digital kitchen scale. Measuring by volume can lead to lye-heavy soap which can burn skin.

What is water discounting?

Reducing the amount of water in your recipe (using a 2:1 ratio instead of 3:1) makes your soap trace faster, pop out of the mold sooner, and reduces the risk of glycerin rivers. However, it gives you less time to work with colors and swirls.

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Soap Making Lye Calculator

Calculate lye and water ratio for cold process soap making. Protect your skin and craft the perfect bar of soap.

CRITICAL SAFETY WARNING

Lye (Sodium Hydroxide) is a highly corrosive chemical! It can cause permanent blindness and severe chemical burns. Always use goggles (not glasses), gloves, and long sleeves. ALWAYS pour LYE into WATER. Never pour water onto lye!

Enter your measurements

Olive Oil Amount(oz)

Coconut Oil Amount(oz)

Palm Oil Amount(oz)

Superfat Percentage(%)

Water to Lye Ratio(:1)

Understanding "Trace"

Trace is the point when your oils and lye water have emulsified and will not separate. How you use the water-to-lye ratio above affects how quickly you reach these stages!

Thin Trace

Looks like thin pancake batter. Droplets don't stay on the surface.

Best for: Swirl designs

Medium Trace

Looks like light pudding. Drizzled soap sits neatly on the surface.

Best for: Layered designs, standard bars

Thick Trace

Looks like thick pudding. Keeps its shape when poured or scooped.

Best for: Textured tops, soap frosting

How to Use This Calculator

To make cold process soap safely, you must use the exact amount of sodium hydroxide (NaOH) to saponify your specific oils. Every oil has a unique 'SAP Value' (saponification value). This calculator multiplies your oil weights by their SAP values and adjusts for your superfat preference.

Understanding Superfat

Superfatting means leaving a small percentage of oil un-saponified in the final soap. This makes the soap more moisturizing and provides a safety margin so you never have leftover active lye in your final bar. 5% is the standard superfat amount.