What baker's percentages mean
In baker's percentages, the total flour in a recipe is always 100%. Every other ingredient is written as a percentage of that flour weight. So a dough with 1,000 g of flour and 700 g of water is 70% water, usually called 70% hydration.
Because the percentages refer to flour and not the total, they don't add up to 100. A typical lean sourdough adds up to around 195 to 200%.
The two baker's percentage formulas
- Percentage = ingredient weight ÷ flour weight × 100
- Weight = flour weight × percentage ÷ 100
For 500 g of flour at 75% hydration: 500 × 75 ÷ 100 = 375 g of water. For 2% salt: 500 × 2 ÷ 100 = 10 g.
Worked example: a sourdough country loaf
| Ingredient | Weight | Baker's % |
|---|---|---|
| Bread flour | 450 g | 90% |
| Whole wheat flour | 50 g | 10% |
| Water | 375 g | 75% |
| Levain (100% hydration) | 100 g | 20% |
| Salt | 10 g | 2% |
| Total dough | 985 g | 197% |
The two flours together make the 100%: 90% bread flour and 10% whole wheat. Water is 75%, levain 20% and salt 2%. The total, 197%, is useful for scaling.
Our convention: levain on top
There are two common ways to treat the starter. On this site, percentages are calculated against the flour you add to the bowl, and the levain gets its own line. Most home recipes are written this way, and it keeps the numbers simple.
The levain also contains flour and water, though. A 100 g levain at 100% hydration holds 50 g flour and 50 g water. Counting those in gives the overall hydration:
| Flour | Water | Hydration | |
|---|---|---|---|
| Added to the bowl | 500 g | 375 g | 75% |
| From the levain | 50 g | 50 g | - |
| Overall | 550 g | 425 g | about 77% |
When you compare recipes from different sources, check which convention each uses. A recipe that says 80% overall hydration may feel very similar to one that says 75% with 20% levain on top.
How to scale a bread recipe
To make a dough of a particular total weight, divide that weight by the total percentage to find the flour, then work out everything else.
- Choose the dough weight. Two 900 g loaves need 1,800 g of dough. Add 2 to 3% for losses in the bowl: about 1,850 g.
- Find the flour. 1,850 ÷ 1.97 = about 939 g. Round to 940 g.
- Multiply out. Water 75% = 705 g. Levain 20% = 188 g. Salt 2% = 18.8 g, call it 19 g.
The calculator does this arithmetic for you.
Typical baker's percentages for bread
| Ingredient | Usual range | Notes |
|---|---|---|
| Water | 60 to 90% | Sandwich loaves at the low end, focaccia at the high end. Wholegrain flour absorbs more. |
| Levain | 10 to 25% | Less levain means a longer, slower bulk ferment. |
| Salt | 1.8 to 2.2% | 2% is standard. Below about 1.5% bread tastes flat and ferments fast. |
| Fat | 0 to 10% | Butter or oil softens crumb and crust. |
| Sugar or honey | 0 to 6% | Adds softness and browning in tin loaves. |
Why baker's percentages are worth learning
With percentages you can see at a glance that one recipe is wetter than another, halve or triple any recipe without errors, and change one thing at a time when you experiment. When a loaf goes wrong, the troubleshooting guide often points to one of these numbers.
Baker's percentages FAQ
Why don't baker's percentages add up to 100%?
Every ingredient is measured against the flour, not the total dough weight. Flour is 100% and everything else is added on top, so a lean sourdough totals around 195 to 200%.
What does hydration mean in bread?
Hydration is the water weight as a percentage of the flour weight. 375 g of water with 500 g of flour is 75% hydration.
Should the levain count towards hydration?
It depends on the convention. Recipes here list the levain separately, so 75% hydration with 20% levain works out at about 77% overall hydration once the levain's own flour and water are counted. The calculator shows both figures.