A preferment worksheet needs two linked allocations: the flour and water prepared ahead, and the flour and water left for the final dough. The Whatson Preferment Calculator keeps those amounts within one total formula.
It also allocates an entered yeast percentage to the preferment flour. The tool does not select a poolish or biga method or assume a final mix yeast addition.
Define the flour share before the preferment hydration
Enter total formula flour, total target hydration and the percentage of that flour assigned to the preferment. Its own hydration sets how much of the total water is used there.
The preferment yeast field uses preferment flour as its basis. Salt uses the total flour basis and is allocated to the final mix in this worksheet.
A 30% prefermented flour example
Use 1,000 g total flour, 65% overall hydration, 30% prefermented flour, 100% preferment hydration, 0.2% preferment yeast and 2% salt.
| Ingredient | Preferment | Final additions |
|---|---|---|
| Flour | 300 g | 700 g |
| Water | 300 g | 350 g |
| Yeast | 0.6 g | 0 g |
| Salt | 0 g | 20 g |
The checked prepared preferment mass is 600.6 g. The complete formula mass is 1,670.6 g. That complete total already includes the preferment.
Do not add a guessed final yeast quantity
A zero in the final yeast row means no final mix yeast was specified by this tool. It does not assert that every prefermented bread requires no additional yeast.
If your established formula includes another addition, account for it outside this schedule or use a separate full ingredient worksheet. The displayed total would need that mass added explicitly.
Keep the water allocation feasible
The target formula in this example contains 650 g water altogether. Increasing preferment hydration increases the water already assigned to the preferment and reduces the fresh final addition.
If the preferment consumes more than the formula’s water budget, the calculator reports an invalid combination. It cannot rescue that plan by inventing a negative water addition.
Sourdough Recipe Calculator provides a similar flour and water split for prepared starter without this preferment yeast field. Baker’s Percentage Calculator can rescale a separately recorded complete formula from a flour target.
Save the preferment flour share, its hydration and the yeast basis together. Preparation duration, room temperature, yeast type and readiness are method decisions that the gram allocation does not determine.