The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Correct me if I'm wrong - bakers formula

Juergen's picture

Correct me if I'm wrong - bakers formula

I've never been good at math but decided to make a bakers formula spreadsheet based on the Bread Bakers Guild format. This in order to make it easier for me to work with bakers formulas. 

Now that I'm ready for baking with it, I'm just looking for a confirmation that what I'm doing is right. Below is the formula with which I want to bake this weekend. It's a basic 2-stage levain/sourdough formula using white wheat flour only. The goal is 1,5 kg of dough (1501 grams to be exact) with 25% levain/sourdough starter at 100% hydration.

The thing that still brings some doubt to my mind is wether or not it is correct to add 452 grams of levain/sourdough starter to my final dough (or should it only be 226 grams??).

Oh, and for those who want a copy of the Excel spreadsheet, just send me a message with your email adress and I will mail it to you.





mwilson's picture

25% sourdough. 25% of what?

Usually the leaven as a whole (flour and water) is treated as an ingredient and it's percent of use is based upon where you add it (ie. the dough which your making where flour is 100%). So I would talk about the sourdough being 25% of the flour used to make the final dough.

You have calculated 25% where only flour contributed from the leaven is 25% of the total flour used, hence your confusion. So yes 452grams but the way you have decided upon 25% is incorrect. Your use of leaven is actually 67%! (452/678)

Hope this helps.



fancy4baking's picture

When you talk 25% preferment, it means 25% sourdough of the 100% flour you have in your recipe. So taking into account the numbers in your table, if we consider the ratio of sourdough of 452 gr. in relation to total weight of 1501 that gives us  nearly 31%.

But if we take the 452 gr. versus the 904 gr of flour (which is i think not right) this will make the ratio of sourdough versus flour approx. 50%.

Another possibility, if you consider the sourdough versus the flour in the final dough 678 gr. (which is not right, cos that will leave the amount of flour within the sourdough itself out) in this case your sourdough ratios in relation to flour in the final dough would be 452/678=66.67%.

The ratio of sourdough within the dough has to be determined in relation to the final over-all dough which is in your case 1501 gr., that would leave us with 452/1501= approx. 31%

In either case, i think 31% could be either ok or too much, depending on two factors: first- how strong your sourdough is or how acidic, second: the ambient temperature where you live. Where i live 31% sourdough within final dough is surely detrimental at the time when temperature now is approx. 30 degrees C.  So if the temperature where you live is relatively warm, i suggest you go lower than 31% sourdough. 


azmar's picture

I've been trying to learn the BBGA formula format too. Based on my understanding, you would use 25% of the flour (in your case, 226g) in the levain, then add the whole levain to your final dough (452g).

BTW "total levain preferment %" in Juergen's spreadsheet refers to the percentage of flour that is prefermented - i.e. (weight of flour in starter/total weight of flour), NOT (total weight of starter/total weight of flour), which might be a point of confusion here.

For what it's worth, I plugged the flour/water/salt numbers into my own spreadsheet and came up with pretty much the same numbers:

I find it helpful to calculate the amount of "seed" starter I need too, since I usually keep a very small amount. I also factor the water and flour in the seed starter into the total formula. I think my approach doesn't strictly conform to the BBGA format, but it's helpful to me.

thomaschacon's picture
thomaschacon (not verified)

You labeled it as "total levain preferment %", but the label should be "Total Fermented in Levain", which is 25%. (226/904). I usually label it "Total Flour Fermented in Levain"


Yes, you bring the entire amount of levain over to final dough column.


What's confusing others in the thread is that they think you want to calculate "Total levain preferment %", which you don't.

It's the label causing the confusion.

When you change it to "Total Fermented in Levain", your calculations will be correct.


I shouldn't even comment on the "Total levain preferment %" because the BBGA format doesn't calculate baker's percentages for Final dough ingredients.

It's too confusing.

Take that 66.7% calculation.

That's confusing.

You'd take one look at that number and say, "Whoa! Something's wrong here! I know 66.7% of my final dough is not levain!"

And it isn't.

It's 30.1%.

That's why the BBGA doesn't calculate baker's percentages for Final dough ingredients.


Awesome that you're trying to learn the BBGA format.

You can change the entire dough profile and/or create entirely new breads in seconds with this format.


If you want to share your spreadsheets or PDFs, check out Dropbox:

If puts a folder on your desktop. You drag files to the folder. You right-click the file and select "Copy Public Link". It gives you a URL (a public link) to the file. Paste that URL into your post. You're done. And it's free for 5 GB. (I once got 100 requests for a Excel file in email. That wasn't fun!)

Not sure if it's Floyd approved, but he hasn't said, "Bad dog! Don't do that!" yet. :)

Juergen's picture

I am using Google Drive, here's the public link to the file, anyone can save, edit and share this. 

Cheers, Juergen

Juergen's picture

Thanks everyone for your quick and thorough replies. I'm sorry for the confusion I caused (English is not my native language :-) 

What I am indeed trying to achieve in this formula, is to calculate the amount of flour that is fermented in the levain in relation to the total weight of all flour in the formula, which is 904g.

Since the total weight of all flour in the formula is 904g, the total weight of 25% of all flour (the part that is fermented in the levain), is 226g. Because the levain has a 100% hydration level, another 226g of water is included in the levain (this makes 452g for the total levain weight).

In the final dough column, the fermented flour in the levain (226g) and the water (which is an integral part of the levain and because the levain is 100% hydration, is also 226g), are first substrated from the total formula. Then in the end, the flour and water which are part of the levain, are added in the form of 'levain' in the 'final dough' column in the right lower corner. All of this combined adds up to a total final dough weight of 1501g (with which I started in the upper left corner under 'Total dough weight').

It is true that the total percentage of the levain in relation to the total dough weight is 30.1%, but that is not what I was trying to calculate.

The formula would be like this. I guess this is correct??



thomaschacon's picture
thomaschacon (not verified)

Looks good, Juergen.

The great thing about this format is how the math balances. If the final dough column weight does not equal total dough weight, you know you've made a math I did yesterday with a formula that had 190 g of salt instead of 19! :D