Soap Planning
This calculator helps plan cold process and hot process soap batches. It follows a simple idea. Each oil needs a known amount of alkali. The oil weight is multiplied by its SAP value. Then the lye discount is applied as superfat. The final amount is adjusted for purity, because flakes are rarely one hundred percent active.
Water Control
The tool is built for careful planning. You can enter many oils, choose units, select alkali type, and set water by three methods. Use oil percentage when you want a traditional planning style. Use lye concentration when you want tighter control. Use water to lye ratio when you follow a fixed recipe habit.
Reading Results
The result table gives the lye need, water amount, scent weight, additive weight, and final batch estimate. It also shows oil percentages and weighted soap profile numbers. These numbers are not promises. They are planning statistics based on stored averages. Supplier data, age, and processing can change real values.
Safety Notes
A low superfat can make a harsher bar. A very high superfat can reduce bubbles and may shorten shelf life. A high water amount gives more working time, but the bar may need longer curing. A low water amount may trace faster. It can help detailed designs, yet it can also surprise beginners.
Always check safety before mixing. Wear gloves, eye protection, sleeves, and work with fresh air. Add lye to water, never water to lye. Use heat safe containers. Keep children and pets away. Label every container before use.
Batch Records
For best results, weigh everything with a digital scale. Do not use kitchen measuring cups. Review the oil list before downloading the record. Save the CSV for logs. Save the PDF for a batch sheet. Test small batches when using a new oil, scent, or supplier. This keeps each batch controlled, repeatable, and easier to improve.
The example table shows a balanced starting recipe. Change the oils to match your pantry. The calculator will update every share and total. If a supplier lists a different SAP value, enter it as custom oil data. That small step improves accuracy. Keep notes about cure time, bar feel, lather, and weight loss, and test again.