Baking
The baking maths: tin sizes, dough hydration and brines.
15 calculators in this section
- Cake Tin Size ConverterAdjust a recipe for a different size or shape of cake tin.
- Dough Hydration CalculatorConvert hydration percentage to water weight for straight pizza, focaccia and bread doughs (no starter).
- Brine CalculatorSalt and water quantities for brining poultry and pork.
- Cake Serving CalculatorHow many portions a round, square or traybake cake will cut into.
- Pizza Dough CalculatorFlour, water, salt and yeast for any number of pizzas, by style.
- Pizza Dough Ball Weight CalculatorHow much dough per ball, and how big a pizza each ball makes.
- Bread Dough CalculatorA full bread recipe scaled to your tin, by style of loaf.
- Sourdough Hydration CalculatorTrue hydration once the flour and water inside your starter or levain are counted in, and the water to add.
- Sourdough Starter Feeding CalculatorHow much starter, flour and water to use for any feeding ratio.
- Baker's Percentage CalculatorExpress every ingredient (salt, yeast, fat and sugar as well as water) as a percentage of flour, and scale a full formula up or down.
- Cake Batter Quantity CalculatorHow much batter your tin needs, and how to scale a recipe to fit.
- Buttercream CalculatorHow much buttercream to make for filling, topping or covering a cake.
- Chocolate Ganache Ratio CalculatorChocolate and cream quantities for glaze, filling, truffles or whipped ganache.
- Pastry Quantity CalculatorHow much shortcrust pastry a tin or pie dish needs, with the recipe.
- Traybake and Tin Size ConverterScale a recipe from the tin it was written for to the tin you own.
Scaling a recipe honestly
Batter, buttercream and ganache scale by weight without much drama. Tins do not: going from a 20cm to a 23cm round is a third more area, so it needs a third more batter and a little longer in the oven at the same temperature. Eggs are the awkward one. Scale to the nearest whole egg and adjust the liquid slightly rather than trying to split one.
Hydration and baker's percentage are not the same
Dough hydration is water against flour for a straight dough. Sourdough hydration counts the water and flour inside your starter as well, which is why the same recipe can read differently. Baker's percentage describes the whole formula with flour at 100%, so you can compare or rescale any recipe. Each has its own calculator here rather than one that quietly mixes the three.
Questions and answers
Common questions about baking calculations
Does changing tin size really mean I have to change the baking time?
Yes, in most cases. A wider, shallower tin bakes faster than the one a recipe was written for, and a smaller, deeper tin takes longer, even though the oven temperature stays the same.
Always test with a skewer or by listening for a hollow sound rather than relying on the original time alone.
Why do bakers use percentages instead of cups or spoons?
Baker's percentages express every ingredient as a share of the flour weight, which is always 100%. That makes recipes scalable to any batch size and directly comparable with each other, in a way that cups and spoons never are.
What does hydration mean in bread and pizza dough?
Hydration is the water weight as a percentage of the flour weight. A higher hydration gives a wetter, stickier dough and an opener crumb; a lower hydration gives a stiffer dough that's easier to shape by hand.
Why does a 23cm tin need so much more mixture than a 20cm tin?
Because the area of a tin (the figure that determines how much mixture it holds) grows faster than its width. A modest-looking increase in diameter or side length can mean a much bigger jump in area, which is why swapping tins isn't as simple as it first looks.
Can eggs be scaled accurately when a recipe is resized?
Broadly yes, eggs scale in proportion with the rest of a cake recipe. In practice you often need to round to the nearest whole or half egg, since a recipe can call for a fraction of an egg that you can't measure out directly.
When should I weigh baking ingredients rather than measure them by volume?
Always, where you can. Flour, sugar and water measured by weight are far more consistent than a cup or spoon measurement, and every calculator here works in weights for that reason. It's the main reason two people's versions of the 'same' recipe can turn out differently.
Does a starter count towards a sourdough recipe's hydration?
Yes. A sourdough starter is itself flour and water, and both parts count towards the finished dough's true hydration, not just the water added separately at the mixing stage.
Sourdough Hydration CalculatorSourdough Starter Feeding Calculator
How much icing or ganache should I make for a cake?
It depends on the cake's size, how many layers it has, and whether you're filling, topping or fully covering it, covering the sides as well as the top needs considerably more than a top-only finish.
Guidance
Guides for this section
- Cake Tin Sizes and Recipe ScalingHow to bake a recipe in the tin you actually own: matching area rather than width, adjusting batter quantity, and what happens to the baking time.
- Understanding Dough HydrationWhat a hydration percentage means, why sourdough is counted differently once a starter is involved, and how baker's percentage ties the whole formula together.