The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Bakers Math.

mij.mac's picture

Bakers Math.

The only thing that makes bakers math complicated is some do it one way and others another but essentially both make the same assumption.  The assumption is that the main flour from the recipe is king and all other ingredients bow to it. Also you must remember that baker’s math is about weight. You can't work baker’s math with volume. 

So how do you work it out?  

1, To get the number of the king divide 100 by the main flour. Write this number down as all other ingredients must bow to it. 

2, Multiply every ingredient in the recipe by the king's number. That's it. It really is that simple.  

So why all the confusion?  

It really comes down to what you decide is 'the main flour'. Do you include flour from the starter? Do you include other types of flour you are going to use, for example rye? To confuse things just a little more some will mix real percentages in, but don't worry about this, always make the assumption that it is pure baker's math and if the author is worth the salt in the recipe they will explain the differences.


 The king's number is  100/596 = 0.1677

Starer   Flour     Water   Salt      Total

20g         596g       394g       12g         1000g

3%       100%         66%       2%          168%



bwraith's picture

I posted an example (html) of breaking down the recipes in the BBA (Reinhart) and in Artisan Baking (Glezer) using baker's percentages in my preferred format. You can also download the xls spreadsheet the example came from.

The styles for baker's math differ quite a bit from one author to another. I much prefer those who put the total flour in the recipe, including preferments, rye, and any specialty flours, as "king", i.e. 100%. However, few seem to do that. I imagine this is because they are trying to give percentages that are easy for just scaling the recipe, so the preferment is most often just a percentage of the flour in the recipe - not including the flour from the preferment. However, to understand a recipe, it seems to me it's better to see how much flour and water comes from each component of the overall recipe as a percentage of total flour. It makes sense to also look at the hydration percentages in the preferments to understand how firm they are.

Although the Glezer book is absolutely great, one thing I don't like so much is the way the baker's percentages are done, and there is incomplete or at least hard to find information there about just what percentages she's using in some cases. It makes understanding what's going on in the recipe a little more difficult, although she makes up for it with very good instructions. In fact, her instructions for dough handling seem better to me than what appears in the BBA, as much as I like the BBA. In the BBA, there is more complete and well presented baker's percentage information. The best versions of baker's percentages are in Hamelman's Bread, as far as I'm concerned, where he gives a couple of different views if the percentages all in a table with the recipe.

I hope this example may be helpful as a discussion piece, even if I don't include much explanation at the moment. Basically, I like to look at the overall hydration, yeast, salt percentages. Also, the individual hydration of each preferment is very useful. And, a lot can be understood about a recipe by seeing what proportion of total flour is contributed to the recipe by each preferment.

I would find it interesting to know what others feel helps in understanding how a recipe is put together and how to modify or convert it in various ways. Although I don't show it in this particular example, I look at this same sort of spreadsheet to figure out how to convert a recipe to sourdough.

Sorry if there are errors in it, which is certainly a possibility, but I'll correct them and repost if so.


bottleny's picture

"Basically, I like to look at the overall hydration, yeast, salt percentages. Also, the individual hydration of each preferment is very useful. And, a lot can be understood about a recipe by seeing what proportion of total flour is contributed to the recipe by each preferment."

I agree with you. I also like to know the overal hydration, including the amount of flour and water used in the Starter, especially when the preferment is not a small portion. It's all right to take it as an "ingredient", for the example in the first post, since the starter is only 20g.

Squid's picture

That explanation is very simple to understand. Thank you.

mij.mac's picture

Thanks Squid, 

that was the idea. Glad I got it across.

KipperCat's picture

I'm glad you got it across, too! :D This concept is new to me - just since hanging out here the past few months. It's great to find this lesson on the site today when I wanted to check out some percentages.