The only baker's math calculator that works in both directions — convert weights to percentages OR enter percentages to get exact ingredient weights for any batch size. True sourdough hydration, 6 recipe presets, yeast conversion, and preferment % included.
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Verified: King Arthur Baking Professional Standards & Bread Bakers Guild of America — April 2026
Enter your recipe ingredient weights in grams. All other ingredients are calculated as a percentage of the total flour weight (flour = 100%). Load a preset to get started instantly.
Quick Recipe Presets
IngredientWeight (g)Type
Used to calculate true dough hydration
True Dough Hydration
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Ingredient
Weight (g)
Baker's %
Type
⚠️ Disclaimer: True hydration accounts for water in sourdough starter at the selected hydration percentage. For other preferments, add their flour and water as separate ingredients.
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Enter your baker's percentages and choose a target to scale by. Get exact ingredient weights for any batch size — one loaf, ten loaves, or any total dough weight.
e.g. 500g flour = one standard loafEnter a valid target amount.
Flour in each loaf
IngredientBaker's %Type
Total Dough Weight
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Ingredient
Baker's %
Weight (g)
Type
⚠️ Disclaimer: Flour is always 100% in baker's math. All other percentages are relative to total flour weight — they do not sum to 100%. When scaling by total dough weight, flour is derived by dividing target by the sum of all ingredient percentages.
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Calculate true sourdough dough hydration accounting for the flour and water already inside your starter. Most calculators miss this — ours gets the accurate number.
Flour added to dough (not in starter)Enter flour weight.
Water added to dough (not in starter)Enter water weight.
True Dough Hydration
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⚠️ Disclaimer: True hydration splits starter into its flour and water components at the selected hydration percentage. If your starter has a different hydration, select the closest option.
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Sources & Methodology
Baker's percentage calculations follow the professional standard established by the Bread Bakers Guild of America and King Arthur Baking's professional curriculum. True sourdough hydration accounts for flour and water contributions from the starter. Preset formulas are based on validated professional recipes from published culinary standards.
// Core baker's math formulas Baker's % = (Ingredient g / Total flour g) x 100 Ingredient weight = Flour g x (Baker's % / 100) Flour (from dough wt)= Target dough / (Sum of all % / 100) True hydration = (Water + Starter water) / (Flour + Starter flour) x 100 Starter flour = Starter / (1 + Starter hydration as decimal) Starter water = Starter - Starter flour
The Complete Guide to Baker's Percentage and Baker's Math
Baker's percentage — also called baker's math, baker's formula, or baker's percent — is the universal language of professional bread baking. Once you understand it, scaling any recipe to any batch size takes seconds, comparing bread formulas becomes intuitive, and the effect of changing any single ingredient becomes immediately predictable. Every professional bakery, every bread baking school, and every serious home baker works in baker's percentages.
Why Baker's Percentage Beats Regular Percentage Every Time
In regular percentage math, all parts sum to 100%. In baker's math, flour is always 100% and every other ingredient is a percentage of that flour weight. A typical artisan sourdough recipe shows: 100% flour, 75% water, 2% salt, 20% sourdough starter — totaling 197%. This is correct in baker's math, and intentional by design. The advantage is profound: the hydration percentage always tells you the exact water-to-flour ratio regardless of batch size, and 2% salt always means the same saltiness whether you make one loaf or one hundred.
To scale any recipe using baker's percentages, you need only one number: your target flour weight. Multiply each ingredient's percentage by that flour weight divided by 100 to get exact gram weights for any batch. This is why bakers from Tokyo to London to Buenos Aires can share a formula written purely as percentages and reproduce identical bread at any scale without conversion.
Dough Hydration: The Single Most Important Baker's Percentage
Hydration — the baker's percentage of water — controls more about your bread than any other variable. It determines dough handling difficulty, crumb openness, crust thickness and crispness, oven spring magnitude, and fermentation rate. Understanding your target hydration before mixing is fundamental to predicting your final result.
Hydration %
Dough Feel
Crumb Character
Typical Breads
Skill Level
55–60%
Firm, dry, non-sticky
Dense, tight, uniform
Bagels, pretzels, some baguettes
Beginner
62–67%
Smooth, slightly tacky
Medium, good structure
Sandwich loaves, rolls, pizza
Beginner
70–75%
Tacky, moderate stickiness
Open, airy, irregular holes
Country sourdough, rustic loaves
Intermediate
76–82%
Wet, sticky, requires technique
Very open, large holes
Ciabatta, high-hydration sourdough
Advanced
80–88%
Very wet, almost flows
Extremely open, pillowy
Focaccia, no-knead loaves
Advanced
True Sourdough Hydration: The Calculation Most Bakers Get Wrong
The most common mistake in sourdough hydration calculation is forgetting that your starter contains both flour and water. If your recipe calls for 500g flour, 350g water, and 100g sourdough starter at 100% hydration, the apparent hydration from main recipe water looks like 70% (350/500). But that 100% hydration starter contains 50g flour and 50g water, significantly changing the true picture.
True hydration = (350g water + 50g starter water) / (500g flour + 50g starter flour) × 100 = 400/550 × 100 = 72.7%. The dough is 2.7% wetter than it appears from main recipe water alone. At high hydrations above 75%, this difference can be the gap between a workable dough and an impossibly sticky one. Our sourdough hydration tab calculates this precisely, accounting for any starter hydration percentage.
Standard Baker's Percentage Formulas for 6 Classic Breads
These are the verified professional formulas loaded as presets in the calculator above. Each represents decades of refinement by professional bakers and is expressed in baker's percentages for unlimited scaling.
Converting a Recipe to Baker's Percentages: Step by Step
Step 1: Identify all flour in the recipe — this is the 100% baseline. If using multiple flour types, add them all together for the total flour base. Step 2: For every other ingredient, divide its weight by total flour weight and multiply by 100. That is its baker's percentage. Step 3: If using sourdough starter, identify the starter's hydration to properly split it into its flour and water components for true hydration calculation. Step 4: Verify the salt percentage falls between 1.8–2.2%, the hydration is what you intended, and yeast or starter percentage matches your desired fermentation timeline.
Yeast Conversion: Instant, Active Dry, and Fresh
Not all yeast types have equal potency. Instant dry yeast (IDY) is the most convenient for home baking — it does not need to be pre-dissolved and is approximately 25% more active than active dry yeast (ADY). Fresh yeast (compressed yeast) is three times less potent per gram than instant yeast, making it the largest-quantity type. Conversions: multiply instant yeast amount by 1.25 for active dry equivalent; multiply instant by 3 for fresh yeast equivalent. In baker's percentages, a standard 0.5% instant yeast formula equals 0.625% active dry or 1.5% fresh yeast. For overnight cold retardation, reduce to 0.1–0.2% instant yeast to prevent over-fermentation.
Baker's Percentage for Enriched Breads, Cookies, and Pastry
Baker's percentage is not limited to lean bread. Every baked good with flour as its structural base benefits from baker's math. For cookies, flour is 100%, butter 50–60%, sugar 40–60%, eggs 15–20%. For brioche, flour 100%, butter 50%, eggs 50%, sugar 15%, milk 15%. For pie pastry, flour 100%, fat 50–65%, water 15–25%. The system scales identically regardless of whether you are making one dozen cookies or twenty — multiply each percentage by your target flour weight divided by 100.
Frequently Asked Questions
Baker's percentage expresses every ingredient as a percentage of total flour weight (flour = 100%). It makes recipes universally scalable and comparable. A baker can look at 75% hydration, 2% salt, 0.5% yeast and instantly know the dough type, handling requirements, and expected texture without knowing the actual gram weights. It is the standard communication format at every professional bakery, culinary school, and bread competition worldwide.
Formula: Baker's % = (Ingredient weight / Total flour weight) x 100. Add up all flour types to get total flour (= 100%). Divide each other ingredient by total flour weight and multiply by 100. Example: 1000g flour, 720g water, 20g salt, 10g yeast. Baker's percentages: flour 100%, water 72%, salt 2%, yeast 1%. Do not expect them to add up to 100% — they will total 175% in this case, which is correct.
Start at 65 to 68% true hydration. At this level the dough is slightly tacky but manageable, holds its shape well during shaping, and produces a pleasing open crumb with crispy crust. Avoid starting above 72% true hydration as a beginner — the dough will be sticky, hard to shape, and frustrating without practiced technique. Once you can confidently shape and score a 68% hydration loaf, increase by 2 to 3% increments until you find your preferred working hydration.
Almost certainly because you are not accounting for the water inside your sourdough starter. Most recipes state hydration as recipe water only, ignoring starter water. A 100% hydration starter adds equal amounts of extra water and flour to your dough. For 100g starter (100% hydration): add 50g flour and 50g water to both totals before calculating true hydration. Use our Sourdough Hydration tab to get the accurate true hydration for any recipe. This is the most common baker's math mistake.
Multiply all ingredients by 2 — baker's percentages stay identical. For a one-loaf recipe: 500g flour, 375g water, 100g starter, 10g salt. For two loaves: 1000g flour, 750g water, 200g starter, 20g salt. The hydration, salt percentage, and starter percentage remain the same at any scale. This is the core power of baker's math — the formula never changes when you scale, only the gram weights change.
The professional standard is 2% of flour weight. Below 1.8% bread tastes flat and bland — salt is not just a flavor agent but a gluten strengthener and fermentation controller. Above 2.5% it starts tasting noticeably salty. For a 500g flour recipe: standard salt = 10g. For sourdough the 2% standard applies. For focaccia 2.2% is typical. For enriched brioche 1 to 1.5% as butter and eggs add savory notes.
The standard range is 10 to 25% of flour weight. 10% produces slow fermentation of 8 to 12 hours at 24°C with more sour flavor from extended activity. 20% is standard for a 4 to 6 hour bulk fermentation at room temperature. 25% or more is fast for same-day baking. In hot weather above 27°C reduce to 10 to 12% to avoid over-proofing. In cool kitchens below 20°C use 20 to 25% or slightly warm your water to keep fermentation active.
A poolish is equal weights of flour and water (100% hydration) plus a tiny 0.1 to 0.5% of yeast, fermented 12 to 16 hours at room temperature before adding to the main dough. If your recipe uses 1000g total flour and the poolish contains 300g flour: prefermented flour percentage = 30%. The poolish also contains 300g water. When calculating the main dough, subtract poolish flour and water from the recipe totals — if recipe needs 720g total water and poolish has 300g, main dough gets 420g added water.
Instant yeast to active dry: multiply by 1.25 (active dry is 25% less potent per gram). Instant yeast to fresh yeast: multiply by 3 (fresh yeast is 3x heavier for equivalent activity). In baker's percentages: 0.5% instant = 0.625% active dry = 1.5% fresh yeast. For overnight cold-retard fermentation, reduce any yeast type to 0.1 to 0.2% instant equivalent. Never add active dry yeast to cold water — it needs warm liquid above 38°C to activate properly. Instant yeast goes directly into dry ingredients.
Neapolitan pizza: 100% 00 flour, 56 to 58% water, 2.5 to 3% salt, 0.1 to 0.2% instant yeast. Cold ferment 24 to 48 hours. NY-style: 60 to 63% water, 2% salt, 0.5% yeast. Pan pizza or focaccia-style: 72 to 78% water, 1% yeast, 2.2% salt, 5% olive oil. Sourdough pizza: 65 to 68% water, 15 to 20% starter, 2.5% salt. The key difference between styles is hydration — lower for thinner, crispier crust, higher for thicker, chewier, more open texture.
Sum all baker's percentages as decimals: 1.00 flour + 0.75 water + 0.02 salt + 0.20 starter = 1.97 total. Then flour weight = target dough weight divided by 1.97. For a 900g target dough: flour = 900 / 1.97 = 457g. All other ingredients multiply from that flour weight: water = 457 x 0.75 = 343g, salt = 9.1g, starter = 91g. Our Percentages to Weights tab handles this scaling mode automatically — just select total dough weight and enter your target.
Classic brioche: 100% bread flour, 50 to 60% butter (room temperature, added in cubes after gluten develops), 50 to 70% eggs, 15 to 20% whole milk, 15 to 20% sugar, 1% salt, 2% instant yeast. The high fat and sugar percentages above 100% flour weight is what makes brioche rich, tender, and yellow-crumbed. Gluten must be fully developed before adding butter — rushing this step produces greasy, dense brioche. Total baker's percentages sum to over 200% for classic brioche formulas.
Whole wheat flour absorbs approximately 3 to 5% more water per 10% substitution. Replacing 20% bread flour with whole wheat at the same recipe water will produce a noticeably stiffer dough. Increase water by 3 to 6% to compensate (e.g. 75% hydration becomes 78 to 81% with 20% whole wheat). Rye flour absorbs even more water and produces stickier, less elastic dough — add 5 to 8% extra water per 10% rye substitution. In multi-flour blends, all flour types still sum to 100% and all percentages remain relative to total flour weight.
A standard home loaf at 750 to 800g finished weight uses 450 to 500g flour. For two standard loaves: 900 to 1000g flour. At 75% hydration with 2% salt and 20% starter: 1000g flour produces 1000 + 750 + 20 + 200 = 1970g total dough. Each loaf will weigh approximately 700 to 750g after baking moisture loss of roughly 10 to 15%. Adjust flour up or down based on your pan size, desired loaf weight, and whether you are making free-form or pan loaves.
Yes. Baker's percentage works for any recipe where flour is the primary structural ingredient. Chocolate chip cookies: 100% flour, 60% butter, 50% brown sugar, 30% white sugar, 20% eggs, 1% salt, 1% baking soda, 0.5% vanilla. Classic yellow cake: 100% flour, 100% butter, 150% eggs, 80% sugar, 30% milk, 2% baking powder, 1% salt. Shortcrust pastry: 100% flour, 60% cold butter, 2% salt, 20% cold water. Scale any baked goods recipe by multiplying percentages by target flour weight.