Your Sourdough Recipe Is Confusing. Why Is Water Listed as a Percentage?
A professional bread recipe uses baker's percentages instead of cup-and-tablespoon measurements. Flour is 100%, water is 65%, salt is 2%. What does this mean, and how do you actually bake with it? Baker's math looks mysterious at first, but once you understand it, you'll never go back to traditional recipe measurements for bread. It's infinitely more flexible and infinitely more accurate.
What This Calculator Does
This baker's percentage calculator converts between traditional recipe measurements and baker's percentages, and scales dough recipes to any batch size. You input your desired flour weight, and the calculator shows exactly how much water, salt, yeast, and other ingredients you need using baker's percentages. This removes the guesswork from bread baking, no more "does this dough feel right?" Instead, you have exact targets based on hydration percentage, fermentation time, and proven formulas.
How to Use This Calculator
If you're starting with a traditional recipe, first measure the flour weight by placing your mixing bowl on a kitchen scale, zeroing the scale, and adding flour until you reach the desired weight (bread recipes are easiest in grams, but ounces work too).
Once you know your flour weight, you can calculate baker's percentages for every other ingredient. Most professional bread recipes already use baker's percentages, so you can input them directly into this calculator.
Enter your total flour weight and the baker's percentages for each ingredient (water, salt, yeast, sugar, butter, etc.). The calculator instantly shows how much of each ingredient you need. If you want to make a bigger batch, just increase the flour weight, the calculator adjusts everything proportionally.
This is why professional bakers love baker's math: scaling a recipe from 500g to 1kg is as simple as entering the new flour weight. No more confusing fraction math.
The Formula Behind the Math
Baker's percentages express every ingredient as a percentage of the flour weight. Flour is always 100%, and every other ingredient is expressed relative to that weight.
The basic formula:
Ingredient weight = (Baker's % ร Flour weight) รท 100
Standard baker's percentages for a simple bread:
Let's work through a concrete example. You want to make a loaf with 500g flour, 65% hydration, 2% salt, and 0.5% instant yeast.
Total dough weight: 500 + 325 + 10 + 2.5 = 837.5g
If you want to make double the batch (two loaves instead of one), just double your flour weight to 1000g, and the calculator adjusts everything:
The advantage: the hydration ratio (water to flour) stays exactly the same, so your dough will behave identically, just in larger quantity. One of the biggest mistakes home bakers make is changing ingredient ratios when scaling recipes. Baker's math prevents this entirely.
Hydration percentage is the ratio of water to flour (water weight รท flour weight ร 100). It's the most important percentage in bread baking:
Our calculator does all of this instantly, but now you understand exactly what it's computing.
Building Your Own Bread Formulas Using Baker's Percentages
Once you understand baker's math, you can create custom bread formulas. Start with the base (flour 100%, water 65%, salt 2%, yeast 0.5%), then add variations:
For enriched dough (brioche, dinner rolls):
For whole grain bread:
For sourdough:
Converting Traditional Recipes to Baker's Percentages
If you have a recipe that measures flour in cups and water in milliliters, converting to baker's percentages makes it flexible and scalable.
Example: A recipe calls for 3 cups flour (let's say 375g) and 1.5 cups water (360mL โ 360g).
This is a very high hydration dough, expect a very wet dough with an open crumb.
Understanding Fermentation Times with Baker's Percentages
Baker's percentages, especially yeast percentage, directly affect fermentation speed:
This is why scaling recipes with baker's math is so powerful, the fermentation characteristics stay the same when you scale.
Tips and Things to Watch Out For
Always weigh ingredients for bread. Volume measures vary too much for bread baking. A cup of flour can be 120โ150g depending on how it's packed. Investing in a kitchen scale is the single best thing you can do for bread baking success.
Hydration affects handling. Higher hydration doughs are wetter and stickier. If you're increasing hydration from 65% to 75%, expect to need a slightly different handling technique (more bench flour, gentler shaping).
Salt percentage matters. Most breads use 1.8โ2.2% salt. Less than 1.5% and the bread tastes bland; more than 2.5% and it tastes overly salty. Stay in the standard range unless you have a specific reason to change it.
Instant yeast and active dry yeast percentages are interchangeable. Instant yeast (also called bread machine yeast) is slightly more potent than active dry yeast, but for bread baking percentages, the difference is negligible. Use the same percentage for both.
Sourdough starter replaces commercial yeast entirely. If you're using 20% sourdough starter, you don't need commercial yeast. The starter provides the leavening power.
Frequently Asked Questions
Why use baker's percentages instead of cups and tablespoons?
Baker's percentages are precise, consistent, and infinitely scalable. A cup of flour weighs different amounts depending on how it's packed; a gram is always a gram. Once you have your formula, scaling from 2 loaves to 5 loaves is a simple multiplication.
What's a good hydration percentage for a beginner?
Start with 65โ68% hydration. This creates a dough that's manageable (not too sticky) but produces a nice open crumb. As you gain experience, you can experiment with higher hydrations.
Can I use baker's percentages for other baked goods like cakes?
Baker's percentages work for any baked good, but bread formulas are where they shine because bread recipes stay the same (same ratios of water to flour) across many different loaves and batches. For cakes, which vary more in their ratios, baker's math is less essential but still useful.
How do I know if my dough is the right hydration?
Touch test is helpful: 65โ70% hydration dough should be slightly tacky but not sticky. If you can stretch it thin without it tearing, hydration is likely in the right range. Over time, your hands will know the feel.
What if I want to add ingredients like nuts, seeds, or dried fruit?
These are typically added as percentages too. Sourdough with walnuts might be 100% flour, 75% water, 20% walnuts (20% of flour weight in walnuts). Add these percentages to your flour weight to calculate total ingredient amounts.
Do I need to adjust baker's percentages for different flour types?
Different flours absorb water at different rates. Whole wheat flour typically needs 2โ3% more water than all-purpose flour. Rye flour needs even more. If you change flour type, you may need to adjust hydration percentage slightly, then adjust again based on how the dough feels.
Related Calculators
Use our recipe scaling calculator for non-bread recipes or if you prefer traditional measurements. Our measurement converter helps if you need to convert baker's percentages to cups and tablespoons. The pizza dough calculator is great for scaling pizza dough (which also benefits from baker's math).