Baker's Percentage Explained: How to Scale Baking Formulas by Weight

In a baker’s percentage formula, flour is always 100%, and every other ingredient is expressed as a percentage of that flour weight, not of the total dough. The formula works both ways: percentage = (ingredient weight ÷ flour weight) × 100, and ingredient weight = flour weight × (percentage ÷ 100). A dough with 800 g of flour and 600 g of water is 75% hydration, because 600 ÷ 800 × 100 = 75, even though water is only 600 ÷ 1,424, about 42%, of the finished dough’s actual weight.

This article works through hydration, salt, yeast, fat, and sugar percentages, two full worked formulas with real gram amounts, and the arithmetic for converting a formula to grams at any batch size. For the broader argument for weighing ingredients at all, see why baking needs precision, which covers ratios across all of baking; this article is the deeper, standalone reference for the percentage system itself.

Baker’s Percentages Are Not Ordinary Percentages

An ordinary percentage describes a share of one whole, and every share in the set sums to 100%. If a dough were 40% flour and 60% water by weight of the finished dough, those are ordinary percentages, and they add to 100% because together they account for the entire dough.

Baker’s percentage measures something different: a ratio to a single fixed reference, the flour weight, regardless of how many ingredients are in the formula or how much of the dough each one physically makes up. Because every ingredient is compared to the same flour figure rather than to each other, the percentages can, and usually do, add up to well over 100%.

Take a basic formula: flour at 100%, water at 75%, salt at 2%, yeast at 1%. Add those and you get 178%. That number is not “178% of the dough”; it has no meaning as a share of anything. It is simply the sum of four independent ratios to flour, and its only real use is as a scaling factor, covered later in this guide. This is the detail that trips up people new to the system: seeing percentages that add past 100% and assuming a mistake, when it is how the notation is designed to work.

The Formula, in Both Directions

Every baker’s percentage calculation reduces to one relationship, used forward or backward:

• Finding a percentage from weights: percentage = (ingredient weight ÷ flour weight) × 100
• Finding a weight from a percentage: ingredient weight = flour weight × (percentage ÷ 100)

A small example of each direction. If a formula has 350 g of flour and 28 g of sugar, the sugar percentage is 28 ÷ 350 × 100 = 8%. Reversing it, if that same formula calls for 350 g of flour and a sugar percentage of 8%, the sugar weight is 350 × (8 ÷ 100) = 350 × 0.08 = 28 g. Both directions use the same flour figure; only the division and multiplication swap places.

Hydration Percentage: What It Actually Means

Hydration is water weight divided by flour weight, times 100: the same formula as any other ingredient, just with water as the ingredient in question. It is the most-quoted baker’s percentage because it describes how a dough will feel and handle before you have touched it.

A dough’s hydration number maps roughly onto texture:

• 55 to 62% hydration produces a firm, easy-to-knead dough that holds its shape well. Sandwich loaves and bagels tend to sit in this range.
• 65 to 75% hydration produces a softer, tackier dough that still shapes cleanly by hand. Most everyday artisan loaves fall here.
• 78% and higher produces a slack, sticky dough that spreads rather than holds a stiff shape, worked more by folding than kneading. Ciabatta and other open-crumbed breads use this range.

BAKERpedia’s baker’s percent reference contrasts two ends of that range directly: a dough around 60% hydration “yields denser and closed crumb similar to American-style bread,” while a dough around 80% hydration “often leads to an airy and irregular crumb,” the effect ciabatta is built around.

Calculating hydration from grams. Say you have a formula written only in weights: 420 g of bread flour and 289 g of water. Hydration is 289 ÷ 420 × 100 = 68.8095%, which rounds to 68.8%, a fairly standard everyday-loaf hydration.

Calculating water weight from a target hydration. Going the other way, say you are working with 900 g of flour and want 68% hydration. Water weight is 900 × (68 ÷ 100) = 900 × 0.68 = 612 g.

Salt Percentage: A Common Range, Not a Fixed Rule

Bread formulas commonly run salt between about 1.8% and 2.3% of the flour weight, with 2% as a frequent default. The Perfect Loaf’s introduction to baker’s percentages notes a typical salt figure of “1.8% – 2.3%,” and BAKERpedia’s own worked example uses 2.0%. This is a commonly cited range rather than a universal law: bakers adjust within it and sometimes outside it for taste, and other factors matter too, such as whether the table salt is fine or coarse, since crystal size changes how much salt fills a spoon but not how much a gram weighs.

Salt does more than season. In a yeasted dough it tightens the gluten network and slows yeast activity, which is part of why formulas rarely drop much below 1.8%: dough with too little salt can ferment unevenly fast and taste flat. Pushed much past 2.5%, salt can slow fermentation noticeably and make the loaf taste oversalted.

For 800 g of flour at 2% salt: 800 × (2 ÷ 100) = 800 × 0.02 = 16 g.

Yeast Percentage: How Much for a Straightforward Loaf

Commercial yeast percentages vary more than salt because they depend on how fast you want the dough to rise and which form of yeast you are using. As a rough guide, instant or active dry yeast in a straightforward everyday loaf commonly runs somewhere around 0.5% to 2% of the flour weight. Fresh (cake) yeast is used at roughly double the equivalent dry amount, since it is a less concentrated product; some formulas for sweeter, enriched, or quick-proofed doughs push yeast percentages toward 3 to 4%, which is the level BAKERpedia’s own worked example uses for a shortening-based dough.

The percentage and the fermentation time trade off against each other. A higher yeast percentage rises faster but tends to taste more simply “yeasty.” A lower percentage paired with a longer, often cooler, bulk fermentation gives the dough more time to develop flavor before it is shaped. Either way, dry yeast is potent enough that its percentage is one of the smallest numbers in most formulas.

For the same 800 g of flour at 1% yeast: 800 × (1 ÷ 100) = 800 × 0.01 = 8 g.

Fat and Sugar Percentage: Where Enriched Doughs Differ

A lean dough, bread made from essentially flour, water, salt, and yeast, has no fat or sugar percentage worth mentioning. An enriched dough, such as a sandwich loaf, brioche, or dinner roll, adds both, and their percentages are what separates a plain loaf from a soft, tender one.

Fat percentage (usually butter, oil, or shortening) coats flour proteins and limits gluten development, which softens the crumb and slows staling. A basic enriched sandwich loaf commonly sits somewhere around 5 to 12% fat; richer doughs such as brioche or babka run well past that, sometimes above 30 to 50%, since a large share of the flour’s structure is deliberately being softened by fat.

Sugar percentage (granulated sugar most often) sweetens, holds moisture, slows gluten and egg-protein setting for a more tender crumb, and browns the crust. A basic enriched loaf commonly sits somewhere around 4 to 10% sugar, with sweet doughs for cinnamon rolls or brioche running higher.

Both figures use the same formula as everything else: percentage of flour weight, not of the dough. For a sense of scale, a rich brioche-style enrichment might run butter at 40% and sugar at 15%. For 500 g of flour, that is butter at 500 × 0.40 = 200 g and sugar at 500 × 0.15 = 75 g, roughly ten times the fat percentage of a lean loaf and forty times its sugar percentage, which is why brioche dough handles, proofs, and bakes so differently from a plain sandwich loaf.

Worked Example 1: A Lean Bread Formula

Here is a complete lean bread formula with new figures, worked out in full.

Add the percentages: 100 + 75 + 2 + 1 = 178%. Add the weights: 800 + 600 + 16 + 8 = 1,424 g, which matches 800 × 1.78 = 1,424 g. Both routes to the total dough weight agree, which is a useful check whenever you build a formula by hand.

Worked Example 2: An Enriched Sandwich Bread Formula

Adding butter and sugar to the same flour weight turns the lean formula above into a soft sandwich bread formula.

Add the percentages: 100 + 60 + 2 + 1 + 10 + 8 = 181%. Add the weights: 600 + 360 + 12 + 6 + 60 + 48 = 1,086 g, which matches 600 × 1.81 = 1,086 g. Hydration here is lower (60% instead of 75%) because butter and egg-free enrichment already add softness, so many enriched formulas run a firmer dough than a lean one.

Sanity-Checking a Recipe With Percentage Math

Calculating percentage from grams is also useful for checking whether a recipe you already have looks ordinary. Say a recipe lists 420 g of flour and 14 g of salt with no percentages given. Salt percentage is 14 ÷ 420 × 100 = 3.33%, well above the common 1.8 to 2.3% range covered earlier. That does not make the recipe wrong, some cured or flavored breads do run saltier on purpose, but it flags the figure as worth double-checking against the original source before you bake it at full scale.

Scaling a Formula to a Target Dough Weight

The reason professional formulas are written in percentages rather than fixed weights is scaling: the same formula produces one loaf or a hundred, and the math to get there is the same three steps every time.

Using the enriched sandwich bread formula above (total 181%), scale it up to 2,000 g of finished dough:

1. Find the flour weight. Divide the target dough weight by the total percentage as a decimal: 2,000 ÷ 1.81 = 1,104.97 g. Round to 1,105 g for the kitchen.
2. Multiply each percentage by the flour weight. Using the unrounded 1,104.97 g keeps rounding error from stacking: water is 1,104.97 × 0.60 = 662.98 g (663 g), salt is 1,104.97 × 0.02 = 22.10 g (22 g), yeast is 1,104.97 × 0.01 = 11.05 g (11 g), butter is 1,104.97 × 0.10 = 110.50 g (110 g), and sugar is 1,104.97 × 0.08 = 88.40 g (88 g).
3. Check the total. Adding the unrounded figures, 1,104.97 + 662.98 + 22.10 + 11.05 + 110.50 + 88.40 = 2,000.00 g, exactly on target. Adding the rounded kitchen weights instead gives 1,105 + 663 + 22 + 11 + 110 + 88 = 1,999 g, 1 g under the target purely from rounding each ingredient to a whole gram, close enough to ignore.

The hydration stays at 60%, the salt stays at 2%, and every other ratio holds, so the 2,000 g batch behaves like the 1,086 g version, just bigger. Doing the same scaling with cups (1.5 times ⅔ cup, for instance) would mean rounding several awkward fractions at once, and each rounding decision would nudge a different ratio.

For everyday recipes that are not written in baker’s percentage at all, the recipe scaler applies the same “multiply everything by the same factor” logic without requiring you to build a percentage table first.

Why Professional Bakers Rely on Baker’s Percentage

King Arthur Baking’s professional reference on baker’s percentage gives three reasons bakeries build formulas this way: because every ingredient is weighed, bakers “work with precision using only one unit of measure”; a formula is “quite easy to scale up or down”; and the notation “allows bakers to share a common language” between kitchens that may use completely different batch sizes. BAKERpedia frames the same idea from the food-science side, describing baker’s percent as a method “widely used in baking to calculate the amounts of macro, minor and micro ingredients,” from flour and water down to salt and yeast measured in single grams.

Both points come back to the same practical advantage over cups: weight has no fill method to control for, and grams multiply cleanly at any batch size, while a fraction of a cup does not. A bakery scaling a formula from a 10 kg test batch to a 200 kg production batch is not reworking fractions twenty times over; the flour weight changes, and every ingredient follows the same percentages it always had. A home baker gets the same benefit at a much smaller scale: once a formula’s percentages are set, doubling, halving, or hitting an exact target dough weight for a specific pan is the same three-step calculation shown above, every time.

Quick Reference

• Flour is always 100%; every other ingredient is a percentage of the flour weight, not of the total dough.
• Percentage from weights: (ingredient weight ÷ flour weight) × 100.
• Weight from a percentage: flour weight × (percentage ÷ 100).
• Hydration: water weight ÷ flour weight × 100. Roughly 55 to 62% is firm, 65 to 75% is a typical everyday loaf, 78% and up is slack and wet.
• Salt commonly runs 1.8 to 2.3% of flour weight; yeast commonly runs about 0.5 to 2% for straightforward dry yeast, roughly double for fresh yeast.
• To scale a formula: target dough weight ÷ (total percentage as a decimal) = flour weight, then flour weight × each ingredient’s percentage gives every other weight.

These six lines cover most of what a bread formula written in baker’s percentage asks you to calculate. The rest is a matter of which percentages a given recipe chooses, and every one of them reduces to the same division or multiplication against the flour weight.