Doubling a recipe is easy. Making exactly six 280 g pizza balls, two loaves sized for your bannetons, or one sandwich loaf that fills your particular pan is where most bakers reach for a calculator. The reliable way to do it is to work by weight with baker's percentages: decide how much dough you want, then let the percentages tell you how much of each ingredient to weigh.
Why scale by weight, not by multiplying cups
Multiplying a volume recipe multiplies its errors. Depending on how it is scooped, a cup of flour can weigh anywhere from about 120 g to 150 g, so "3 cups" is somewhere between 360 g and 450 g before you have multiplied anything. Teaspoons of salt and yeast are just as loose, and recipes that call for "1 egg" don't scale neatly to 1.5 times. More importantly, multiplying only gets you a multiple of the original batch. If a recipe makes 873 g of dough and you want exactly 1,000 g, you need a scaling factor of 1,000 ÷ 873 = 1.1455: awkward with cups, trivial with grams.
Baker's percentages turn every recipe into a set of ratios to the flour. If you are new to them, start with baker's percentage explained. The short version is that flour is always 100% and every other ingredient is a percentage of it.
The scaling formula
Add up all the percentages in the formula, then:
total flour = target dough weight ÷ (sum of percentages ÷ 100)
Every other ingredient is the flour weight multiplied by its percentage. Step by step:
- Work out the target dough weight: number of pieces × weight per piece, plus a small allowance for waste.
- Add up the percentages, making sure every ingredient is counted exactly once.
- Divide the target weight by the sum (as a decimal) to get the total flour.
- Multiply the flour by each percentage.
- If the formula has a preferment or levain, work out its flour and water and subtract them from the totals to get the final dough.
Worked example: two 900 g sourdough loaves
The formula is written as a total formula: 100% flour, 75% water and 2% salt, with 20% levain at 100% hydration. Because it is a total formula, the levain's flour and water are already inside the 100% flour and the 75% water, so the levain is not added to the sum:
sum = 100 + 75 + 2 = 177%
total flour = 1,800 ÷ 1.77 = 1,016.9 g
From the totals: water 1,016.9 × 0.75 = 762.7 g, salt 1,016.9 × 0.02 = 20.3 g and levain 1,016.9 × 0.20 = 203.4 g. That levain contains 101.7 g flour and 101.7 g water, which come out of the final dough:
| Ingredient | Total formula | Final dough (what you weigh) |
|---|---|---|
| Flour | 1,016.9 g | 915.3 g |
| Water | 762.7 g | 661.0 g |
| Salt | 20.3 g | 20.3 g |
| Ripe levain | (inside flour and water) | 203.4 g |
| Dough weight | 1,800 g | 1,800 g |
Here is what happens if you add the levain to the sum by mistake. A sum of 197% gives 1,800 ÷ 1.97 = 913.7 g of flour, and once the levain's flour and water are taken back out of the totals, the dough weighs only 913.7 × 1.77 = 1,617 g. That is two loaves of about 809 g, roughly 10% short.
The opposite situation also exists. Some recipes write the starter as an extra ingredient on top of the flour and water, for example 100% flour, 70% water, 20% starter and 2% salt, where the starter's flour and water are not included in the 100% and the 70%. In that style the starter does belong in the sum. The rule is the same either way: count every gram exactly once.
Allow for waste
Dough sticks to the bowl, the bench, the scraper and your hands. Add 1–3% to the target weight: closer to 1% for large batches of firm dough, closer to 3% for small batches of wet, sticky dough. For the loaves above, a 2% allowance makes the target 1,800 × 1.02 = 1,836 g and the total flour 1,836 ÷ 1.77 = 1,037.3 g.
Worked example: four Neapolitan pizzas
Four 260 g balls plus 2% waste is 4 × 260 × 1.02 = 1,060.8 g of dough. The formula is 100% flour, 62% water, 2.8% salt and 0.2% instant yeast (0.6% if you use fresh), a sum of 165%:
- Flour: 1,060.8 ÷ 1.65 = 642.9 g
- Water: 642.9 × 0.62 = 398.6 g
- Salt: 642.9 × 0.028 = 18.0 g
- Instant yeast: 642.9 × 0.002 = 1.3 g
See the Neapolitan pizza formula for the full method and fermentation schedule, or the ready-made batches for 2, 4 and 6 pizzas.
How much dough per piece?
| Bread or pan | Dough per piece | Notes |
|---|---|---|
| Neapolitan pizza, 10–12 in (25–30 cm) | 230–280 g | Thin center, puffy rim |
| New York pizza, 14 in (36 cm) | 300–340 g | Thin, foldable slices |
| New York pizza, 16 in (41 cm) | 400–450 g | Same thickness, bigger pie |
| Bagel | 100–120 g | Go lighter for minis, heavier for deli-style |
| Baguette, home-oven length | 300–350 g | Sized to fit a standard home oven |
| Sandwich loaf, 9 × 5 in (23 × 13 cm) pan | 850–950 g | Less for a flat top, more for a tall dome |
| Focaccia, 9 × 13 in (23 × 33 cm) pan | 900–1,000 g | About 8 g per square inch |
| Boule or batard for a Dutch oven | 750–1,000 g | Match it to your banneton and pot |
Scaling to a different pan
For pan breads, scale by area. A 9 × 13 in focaccia pan is 117 square inches, so 950 g of dough works out to about 8.1 g per square inch. A 10 in round pan is about 78.5 square inches and needs roughly 950 × 78.5 ÷ 117 = 637 g. A 13 × 18 in half-sheet pan is 234 square inches, exactly twice the area, so it takes twice the dough: 1,900 g. The same logic works for loaf pans. Our focaccia and sandwich bread formulas list the pan sizes they were written for.
Scaling yeast, time and temperature
Because every ingredient scales by the same factor, the percentages, including the yeast, stay the same whether you make one loaf or ten. What changes is how the dough behaves:
- Large batches hold heat. A big mass of dough warms and cools slowly and keeps the warmth fermentation produces, so it often runs faster than a small one. Longer machine mixing adds friction heat too. Use the desired dough temperature method to set the water, and consider trimming the yeast slightly for very large batches.
- Small batches lose heat. A single pizza ball's worth of dough cools quickly in a cold kitchen, so keep it somewhere warm.
- Dividing takes time. When you shape twelve bagels, the first is several minutes further along than the last. Bake in the order you shaped.
- Tiny yeast amounts are hard to weigh. If you need 0.3 g, dissolve 1 g of yeast in 50 g of the recipe's water and use 15 g of that mixture, which contains 0.3 g of yeast. Count those 15 g as part of the water.
Rounding
Round flour and water to the nearest gram and salt and yeast to the nearest 0.1 g. Always round the final amounts, never the flour weight partway through the calculation. In the loaf example, weighing 915 g of flour instead of 915.3 g changes nothing you could taste. Small ingredients are more sensitive: rounding the pizza's 1.3 g of yeast up to 1/2 tsp (about 1.5 g) adds roughly 15–20% more yeast, which is still workable but will speed things up a little. If you are converting yeast types at the same time, the yeast conversion guide has the ratios.