Baker's percentage is a notation method indicating the proportion of an ingredient relative to the flour used in a recipe when making breads, cakes, muffins, and other baked goods. It is also referred to as baker's math, and may be indicated by a phrase such as based on flour weight. It is sometimes called formula percentage, a phrase that refers to the sum of a set of baker's percentages. Baker's percentage expresses a ratio in percentages of each ingredient's weight to the total flour weight: For example, in a recipe that calls for 10 pounds of flour and 5 pounds of water, the corresponding baker's percentages are 100% for the flour and 50% for the water. Because these percentages are stated with respect to the weight of flour rather than with respect to the weight of all ingredients, the sum of these percentages always exceeds 100%. Flour-based recipes are more precisely conceived as baker's percentages, and more accurately measured using weight instead of volume. The uncertainty in using volume measurements follows from the fact that flour settles in storage and therefore does not have a constant density. Baker's percentages A yeast-dough formula could call for the following list of ingredients, presented as a series of baker's percentages: {| class=wikitable style="text-align:center;" |- | align=left | flour || 100% |- | align=left | water || 60% |- | align=left | yeast || 1% |- | align=left | salt || 2% |- | align=left | oil || 1% |} Conversions There are several common conversions that are used with baker's percentages. Converting baker's percentages to ingredient weights is one. Converting known ingredient weights to baker percentages is another. Conversion to true percentages, or based on total weight, is helpful to calculate unknown ingredient weights from a desired total or formula weight. Using baker's percentages To derive the ingredient weights when any weight of flour Wf is chosen: {| class=wikitable style="text-align:center;" |- ! align=left colspan=2 | Baker'spercentage || colspan=2 |weights |- ! align=left | ingredient || % || method 1 || method 2 |- | align=left | flour || 100% || align=left | Wf * 1.00 ||align=left | Wf * 100% |- | align=left | water || 35% || align=left | Wf * 0.35 ||align=left | Wf * 35% |- | align=left | milk || 35% || align=left | Wf * 0.35 ||align=left | Wf * 35% |- | align=left | fresh yeast ||