| Ingredient | Baker's % | Grams |
|---|---|---|
| Flour | 100% | — |
| Water | — | — |
| Starter / levain | — | — |
| Salt | — | — |
| Total dough | — | — |
Want the baker's math done for you?
The Sourdough Companion's Formula Lab calculates levain, water and salt to the gram from your flour and hydration — and saves every formula so you can scale, tweak and bake it again.
Try the Formula Lab — freeWhat is baker's percentage?
Baker's percentage is the universal language of bread recipes. Instead of fixed weights, every ingredient is written as a percentage of the total flour, and the flour itself is always 100%. So a recipe at 70% hydration, 20% starter and 2% salt means: for every 100 g of flour you use 70 g of water, 20 g of starter and 2 g of salt. Because everything is anchored to flour, a formula scales perfectly — the same percentages bake one loaf or ten.
How to read it
The percentages do not add up to 100% — they are each measured against the flour, so they routinely total more than 100. Knowing how to calculate baker's percentage lets you compare any two recipes at a glance and dial in your own: nudge hydration up for a more open crumb, raise the starter for a faster rise, keep salt near 2% for flavour and control.
Why true hydration matters
Your starter is itself made of flour and water, so the real hydration of your dough is higher than the water you pour in. This baker's percentage calculator adds the starter's flour and water back into the totals to show the true total hydration — the number that actually predicts how your dough will feel and handle. Many quick calculators skip this step; this one does not.
How this works (the math): water = flour × hydration%, starter = flour × starter%, salt = flour × salt%, and total dough = flour + water + starter + salt. For true hydration, the starter is split into flour and water using its own hydration (a 100%-hydration starter is half flour, half water), then total water ÷ total flour gives the honest figure. Grams are rounded to the nearest whole gram.
These are the same conventions used inside The Sourdough Companion app's Formula Lab: starter and salt as a percentage of the main flour you add, and a true-hydration total that includes the levain's own flour and water.
New to the terms? Browse the Sourdough Glossary → — 100+ science-backed definitions, from baker's percentage and hydration to levain.