Bread Calculator

Using the bread calculator

Start by choosing the unit system, US units (ounces and pounds) or metric (grams and kilograms), then choose what you want to find out. The dough weight box has its own unit menu (oz or g): it follows the unit system whenever you switch it, but you can change it afterwards if your scale reads in the other unit.

• Ingredients for a desired dough works backwards from the weight of dough you want. Enter that weight, the hydration, how much leavening you want and the percentages of salt, sugar and oil. You get the flour, water, sourdough or yeast, and other amounts to weigh out.
• Dough hydration from ingredients takes the weights already in your bowl and tells you the hydration of the dough and the total dough weight. If you use a starter, enter its own hydration so its flour and water are counted properly.
• Sourdough hydration percentage is a quick check for a starter: enter the flour and the water you feed it with and you get the starter's hydration.

For the first two tasks, choose the leavening agent. With a sourdough starter, set the starter's hydration (100% means equal weights of flour and water). With yeast, pick the type and enter the amount for that type: active dry yeast is used at roughly 1.5 times the instant dry amount, and fresh yeast at roughly 3 times. When you change the type, the yeast percentage (and the yeast weight in the hydration task) is rescaled to the new type and rounded to three decimals, so the leavening power stays the same.

The results also say how many small (400 g or 14 oz) and large (800 g or 28 oz) loaves the dough would make. Those are only rough guides to portioning.

How baker's percentages work

Bakers write recipes as percentages of the flour weight, which makes a recipe easy to scale and to compare. The flour is always 100%, and every other ingredient is expressed relative to it.

ingredient % = ingredient weight ÷ flour weight × 100

A dough with 70% hydration holds 70 g of water for every 100 g of flour. A salt level of 2% means 2 g of salt per 100 g of flour. Starter and yeast are given the same way. The percentages add up to well over 100%, which is expected because they are not shares of the total dough.

To find the amount of flour in a dough that has a known total weight, divide the total by the sum of all the ratios. For a dough that is 100% flour, 65% water and 2% salt, the total is 1.67 times the flour weight, so a 1,000 g dough contains about 599 g of flour.

The calculator applies the same idea with extra care for starter and for several additions at once. The flour and water inside a sourdough starter count towards the total flour and total water, so the hydration you enter is the hydration of the whole dough. When salt, sugar and oil are all used, each percentage is measured against the flour that is left once the other additions have taken their share of the dough weight.

Worked example: an 800 g sourdough dough

You want 800 g of dough at 70% hydration, using 20% starter that is kept at 100% hydration, with 2% salt.

1. The starter is half flour and half water, so every 100 g of added flour brings 20 g of starter, containing 10 g of flour and 10 g of water.
2. For 100 g of added flour, the total flour is 110 g. At 70% hydration the total water must be 77 g, of which 10 g comes from the starter, so 67 g of water is added.
3. The salt is 2 g. The batch weighs 100 + 67 + 20 + 2 = 189 g for every 100 g of added flour.
4. Scale to the target: 800 ÷ 1.89 = 423.3 g added flour, 283.6 g water, 84.7 g starter and 8.5 g salt.

Check: the total flour is 423.3 + 42.3 = 465.6 g, the total water is 283.6 + 42.3 = 325.9 g, and 325.9 ÷ 465.6 = 70.0%. The calculator rounds flour up to a whole gram, so it prints 424 g for the flour.

To check a dough you have already mixed, switch to the hydration task. A bowl with 500 g flour, 350 g water, 120 g starter at 80% hydration and 10 g salt weighs 980 g. The starter holds 66.7 g flour and 53.3 g water, so the hydration is (350 + 53.3) ÷ (500 + 66.7) = 71.18%.

How much starter should you use?

Starter is measured as a percentage of the added flour. The calculator accepts 5% to 50%. A small amount makes a slow, tangy fermentation that suits an overnight rise; a large amount works quickly and gives a milder flavor. Around 20% is a comfortable starting point for a loaf you want ready the same day or after an overnight rise at cool-room temperature.

Notice that the water to add falls as the starter share rises, because the starter itself carries water into the dough. The flour column is rounded up, as the calculator does.

Choosing a dough hydration

Hydration is the main control over texture. More water gives a softer, stickier dough and an open crumb; less water gives a firm dough that is easy to shape. The ranges below are rough rules of thumb, and flour type matters, since whole grain flours absorb more water than white flour.

Dough hydration is also a topic for pizza makers, where the numbers differ; see the pizza dough calculator.

Yeast doughs and yeast types

Yeast is dosed far more lightly than starter, usually well under 1% of the flour weight. A slow, cool fermentation needs very little, while a quick dough in a warm room needs more. For equal leavening power, instant dry yeast, active dry yeast and fresh yeast stand roughly in the ratio 1 : 1.5 : 3, so 0.3% instant becomes about 0.45% active dry or 0.9% fresh.

As an example, 1,000 g of dough at 65% hydration with 0.3% instant yeast and 2% salt needs about 597 g flour, 389 g water, 1.8 g yeast and 12.1 g salt. Yeast is counted with the flour when the water is worked out, so the hydration stays at 65% of the flour-and-yeast weight. For conversions between yeast types see the yeast converter.

Measuring sourdough starter hydration

starter hydration = water weight ÷ flour weight × 100

Feeding 100 g of flour with 80 g of water makes a starter at 80% hydration and 180 g in total. A starter fed with equal weights is at 100%, a thick paste is nearer 60% and a pourable one can reach 150% or more. The figure matters, because a wetter starter adds more water to a dough than a stiff one does.

Weigh ingredients rather than measuring cups. A cup of flour varies with how it is packed, which changes hydration noticeably. If you only have volume measures, the cups to grams converter can give a starting estimate.

Scaling, loaf weight and rounding

• Bake loss. Loaves lose around 10 to 15% of their dough weight as steam, so 800 g of dough bakes to roughly 680 to 720 g. Plan the dough weight from the loaf you want.
• Rounding. Flour in whole grams is rounded up and other amounts are rounded to the nearest displayed digit, so the printed numbers can differ from the exact total by a fraction of a gram.
• Scaling a recipe. To make half or double a formula, the recipe converter and scaler multiplies every line, and the recipe converter changes the units.
• Limits. The calculator expects hydration between 10% and 95%, starter between 5% and 50%, and each of yeast, salt, sugar and oil up to 5%.