Baker's Percentage Calculator for Sourdough (Grams to % and Back)
Baker's percentages describe a recipe by weight, with the flour set at 100%. Every other ingredient is written as a percent of the flour. Because it's based on ratios, a recipe in baker's percentages scales to any loaf size.
The rule
ingredient % = ingredient weight ÷ flour weight × 100
and back again:
ingredient weight = flour weight × ingredient % ÷ 100
If a recipe uses more than one flour, add them up: the total flour is 100%, and each flour is its share of that total.
Worked example
A loaf with 500 g flour, 350 g water, 100 g starter and 10 g salt:
| Ingredient | Grams | Baker's % |
|---|---|---|
| Flour | 500 | 100% |
| Water | 350 | 350 ÷ 500 = 70% |
| Starter | 100 | 100 ÷ 500 = 20% |
| Salt | 10 | 10 ÷ 500 = 2% |
| Total | 960 | 192% |
The percentages add up to more than 100% because flour alone is 100%. That total is useful: flour = target dough weight ÷ (total % ÷ 100). For two 960 g loaves (1,920 g of dough) at 192%, you need 1,920 ÷ 1.92 = 1,000 g flour, then 700 g water, 200 g starter and 20 g salt.
The starter's own flour and water
A starter is flour and water too. Baker's percentages as shown above count only the flour you add to the bowl. If you want the true hydration of the whole dough, including what's inside the starter, use the hydration calculator.
Why bakers use it
- Scaling. Change the flour weight and every other amount follows.
- Comparing recipes. Two recipes with 70% water are the same hydration even if one makes a small boule and the other a big batch.
- Spotting mistakes. If salt comes out at 20% instead of 2%, a decimal slipped.
Sources
- Formulas: the definition of baker's percentage (each ingredient as a percent of total flour weight). All numbers above are computed with it.