What to CookCake
How to Make Your Baking Recipe Fit Your Pan Size
Every week, baking expert Alice Medrich will be going rogue on Food52—with shortcuts, hacks, and game-changing recipes.
Today: Alice Medrich's famous brownies are made in an 8-inch pan, but you'll want to make a sheet pan-worth. Here's how you can make that happen with just a little math.
The brownie recipe you want to make calls for an 8-inch square pan, but your only square pan is a 9-inch. Should you risk it? Maybe you want to double or triple a recipe but you aren’t sure which pan to use, or maybe you have a specific large pan but don’t know how many times to multiply your recipe in order to fill it.
The answers to these and similar questions (asked endlessly in cooking classes!) do not involve rocket science, but just enough elementary school math to calculate the area of a square, rectangle, or circle. I love the math (and I’ve included a little math review below if you want to brush up), but I’m sharing my chart in case you don’t have my thing for math.
The handy list below (or some basic math, also explained below) will tell you the surface area of your pan. Once you know the area of any pan, you can compare it to the area of another pan to see how much bigger or smaller it is. You can divide the area of a large pan by the area of a small pan to figure out how many times to multiply a recipe to fill the larger pan with the same depth of batter (more on that later).
Handy list (with the numbers rounded up to the nearest inch):
Area of square/rectangle pans:
- 6 x 6 = 36 square inches
- 7 x 7 = 49 square inches
- 8 x 8 = 64 square inches
- 9 x 9 = 81 square inches
- 9 x 13 = 117 square inches
- 12 x 16 (half-sheet pan) = 192 square inches
Area of round pans:
- 5 inch = 20 square inches
- 6 inch = 29 square inches
- 7 inch = 39 square inches
- 8 inch = 50 square inches
- 9 inch = 64 square inches
- 10 inch = 79 square inches
- 12 inch = 113 square inches
I don’t always have the chart at hand; I often just do the math!
For squares and rectangles: The area of a square or rectangular pan is calculated by multiplying one side times the other side. The area of an 8-inch square is 64 square inches because 8 x 8 = 64; the area of a 9 x 13-inch pan is 117 square inches because 9 x 13 = 117. Easy.
For rounds: The area of a circle equals π times the radius squared. In case you don’t remember, π = 3.14; the radius of a circle is half of its diameter; and squaring means multiplying a number by itself. Ready? To calculate the area of an 8-inch round pan, multiply 3.14 (π) by 4 (because it’s half of 8) times 4. Thus, the area of an 8-inch circle is 3.14 x 4 x 4, approximately 50 square inches. Not so hard!
Just by glancing at the two pans, you might think that a 9-inch pan is very close in size to an 8-inch pan of the same shape, thus making it a reasonable substitute. But if you check the chart, you’ll find that a 9-inch square pan is more than 25% larger than an 8-inch square pan. (The relationship between a 9-inch and 8-inch round pan is similar.) Such a considerable difference will result in a 9-inch batch of very thin brownies that may be over-baked by the time you check them for doneness (because thin brownies bake faster than thick ones). Knowing this beforehand, you can increase the recipe by 25% for results as thick than the original recipe intended. If you want brownies that are even a tad thicker than the original recipe, you can even increase the recipe by 33%.
Let's try an example: How many times should you multiply an 8-inch brownie recipe to fill a 9- x 13-inch pan or a 12- x 16-inch half sheet? To figure this out, divide the area of the larger pan by the area of the 8-inch pan.
- For the 9- x 13-inch pan: 117 divided by 64 = 1.82, which is close enough to 2 that you can confidently double the recipe for the larger pan.
- For the half sheet: 192 divided by 64 is exactly 3, so you can multiply the recipe times 3.
Using similar math, you can calculate how many times to multiply the recipe for a round cake to make a large rectangular sheet cake. And don’t forget that you don’t always have to multiply recipes by whole numbers—it’s perfectly fine to multiply a recipe by 1 1/2 or 2 2/3.
About now, you might be wondering about eggs. It’s nice if you can increase recipes so that you don’t have to deal with fractions of eggs—by increasing a 2-egg batter by 1 1/2 or a 3-egg batter by 1/3 or 2/3, for example—but it is not essential.
Here’s what to do if you multiply a recipe and end up needing part of an egg: Set aside any whole eggs you need. Next, whisk the other egg to blend the white and yolk; weigh it (preferably in grams); then weigh out the fraction of the egg that you need for the recipe and add that to the whole eggs. If you need 40% of a 50-gram egg, that’s 20 grams of the whisked egg. When egg whites and yolks are used separately, weigh and measure them in the same way, but separately. Add leftover egg parts to your morning scramble. See, no waste and still no rocket science!
The chart (or your ability to do the math) is extremely valuable: Use it but don’t be a slave to it. When I make brownies in a large quantity, I like them to be about the same thickness as they are in a small batch, so I stay close to the chart. But, when I increase the dimensions of a birthday cake, I often make it a bit taller than the original (in other words, I round up when multiplying) because the proportions are visually more pleasing. For example, if I am making a 12-inch round cake using a recipe meant for an 8-inch pan, I divide the area of the 12-inch round pan (113) by the area of the 8-inch round (50 inches) and get 2.26. But instead of multiplying the recipe by just 2.26, I might multiply it by 3 so that the cake will turn out tall and lofty. See: Love the chart, but don’t let it bully you!
When you round things up like that, don’t go overboard: Pans should not be filled more than about 2/3 full or batter may overflow. If you do end up with too much batter, scrape the excess into cupcake molds or a mini cake pan—bonus cakes never go uneaten!
When you increase recipes and bake in larger pans, you should anticipate longer baking—anywhere from a little longer if the pans are filled to the same level as the original recipe to considerably longer if you are making the cake taller by filling the pan a bit more. If you are making a smaller amount of the recipe, check earlier than you think you need. And always use a cake tester to check to see if the cake is finished.
Pick up a copy of Alice's new book Flavor Flours, which includes nearly 125 recipes -- from Double Oatmeal Cookies to Buckwheat Gingerbread -- made with wheat flour alternatives like rice flour, oat flour, corn flour, sorghum flour, and teff (not only because they're gluten-free, but for an extra dimension of flavor, too).
Comments (136)
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8 days ago contessa washington
i have a recipe that is for 2-8 inch round cake tins. i want to make a wedding cake that is a three tier 6'', 9'', and a 12'' how can i convert that?
7 days ago Don Brabston
assuming you want each of the 3 tiers in your desired cake to be the same thickness as one of your 8" cake tins, you will need a little over twice as much of the recipe. The total volume of the 2 8" cake pans is 100.5 x h, where h is the height of the cake pan; so if the 8" cake pans are 2" deep, they have a total volume of 201 cubic inches. The 3 tiers, each of height h, will have a volume of 205 x h; so, for h = 2", the 3 tiers have a volume of 410 cubic inches, or a little over twice the recipe for the 2 8" cake pans.
10 days ago Colin
Thank you for this! Extremely useful. I’m just wondering if the oven temperature would need to change when scaling up a recipe?
10 days ago Harsh
Thank you so much it is a very helpful article
about 1 month ago Carla Sitko
I have a recipe that calls for 2, 8" round cake pans. I would like to make 2, 9x13 pans instead. By your math, I should be able to do 1 double batch per 9x13 pan - right? Thank you!
about 1 month ago Don Brabston
I'm not quite sure what you mean by a "double batch per pan", but your 2 8" round pans have a total area of about 100 square inches, while your 2 9"x13" pans have a total area of 234 square inches. So your recipe which fills the 2 round cake pans would not quite fill one of the rectangular pans. Hope this answers your question.
about 1 month ago Denise Musgrove Kellum
need help converting cake recipe from (3) 9" round layers to (3) 10" round layers
Cake (3-9inch layers)
2 box White cake mix
16 oz sour cream
½ c Vegetable oil
6 eggs
15 oz can Cream of Coconut (such as Coco López)
Frosting
16 oz cream cheese
4 Tbsp. milk
2 lbs. Powdered Sugar
2 tsp. Vanilla
4 bags (about 24 oz.) Fresh Frozen Coconut
Please help...need it today ([email protected])
about 1 month ago Don Brabston
Assuming you want the same thickness layers in the 10" layers as in the 9" layers, your new cake will have almost 25% (actually 23.4%) more volume in it. Therefore, you will need about 25% more ingredients, which computes as (for the cake): 2 1/2 boxes white cake mix; 20 ox sour cream; 5/8 c (5 oz) vgetable oil; 7 1/2 eggs; and 19 oz Cream of Coconut. The amount of frosting depends on the surface area, not the volume, of the cake. The relative surface area of the two cakes depends on both the diameter of the cakes as well as the heights (thicknesses) of the cakes. Without knowing the different thicknesses, it's impossible to determine exactly the amount of increase in the frosting recipe. However, let's make an assumption that both cakes are both 8" high (including all three layers). Then the 9" cake has an area of about 707 square inches, and the 10" cake has an area of about 817 square inches, so you will need about 15% more frosting. (This assumes that there is no frosting between the layers. If there is a half inch of frosting between the layers - which means two layers of frosting plus the top surface, then you'll need about 18% more frosting total for the 10" cake as opposed to the 9" cake.)
about 1 month ago Denise Musgrove Kellum
Thank you Don Babston. You really helped me!!
about 2 months ago JuJu
Nothing beats the math, especially when one may have an irregular-sized pan, and the article above is great in explaining area and circumference.
For folks, however, who shy away from the math and want to know the capacity of common-sized baking pans, enter in your browser, the search phrase, "baking pans volume or capacity," to see a few other sites that provide a list for other common sizes and capacities in addition to the ones above.
You'll still need to do a bit of math if comparing capacities, as ecplained in the article, but this may help folks with cup capacity when comparing.
Don't forget that regardless of capacity, fill only 2/3 full as this article states, to prevent over-flow.
2 months ago Sherry Chamberlin
My name is Sherry and I have a question that I hope you can answer for me. I have a recipe that calls for a 9 by 13 pan. I am going to Triple the recipe. See I already know how many batches of the recipe I need, what I need to know is what size pan I need to fit this in. Do you happen to know that answer? I have a pan that is 12 by 18 by 2. That is my biggest pan. Will that be big enough? By the way my dish is not baking it is something that is being cooked on the stove poured into a pan to set and be covered with other stuff. I just do not want to make three separate batches. I cannot triple the batch and then make one pan full and wait to fill the other pans because it is a candy and that cannot be done. I would have to make each batch separately and I'm a disabled woman wanting to combine everything and make it all at once to save energy and time. Any advice on how to do this would be greatly appreciated.
about 2 months ago JuJu
A 9" x 13" x 2" rectangular pan is 117 sq in, which happens to hold ~15 cups. Tripling that amount, of course, is 45 cups.
A 12" x 18" x 2" is 216 sq. Dividing 216 by 117 is ~1.84, which means the 12" x 18" pan holds close to 2 times the amount of the 9" x 13" pan, but not 3 times the amount.
Manufacturers list volume capacity of baking pans in terms of water, but that does not equate to the capacity of various batters, which is why the recommended amount to fill any size pan is 2/3 full of the pan's total volume..
2 months ago Noreen
I have a baking pan that is long and narrow 15 x 6 and 1 inch high. What can I bake in it?
Please help. It says I can bake a pie or anything else that normally goes in a round pan ?
This pan came from Bandwagon?
about 2 months ago JuJu
Aside from volume or pan's capacity, what is baked in it depends on whether the pan is light or dark metal, or glass. With glass, decresse oven temp by 25 degrees and cook a bit longer to avoid over-browning or a burnt finishef product.
With a light-metal pan, remember, baked goods bake and brown more slowly as with a darker pan heat is absorbed more quickly.
Think light-colored clothing on a hot, summer day reflects heat and keeps one cooler, while datk-colored clothing absorbs heat and keeps one hotter.
3 months ago Karen
Thank you for this very informative and practical post. I need help converting a recipe for 7” angel food/tube pan to a 9” angel food/tube pan (that’s the size I own). I’m thinking buying a 7” pan may be easier-lol. Thanks for your help!
3 months ago Don Brabston
The simple answer is that you'll need about 65% more batter for the 9" pan than the 7" pan (9 divided by 7, quantity squared). But watch the assumptions that go into this simple answer: it assumes that the center holes in the two pans are in the same proportion to the outer dimensions (i.e., if the center hole in the 7" pan is 2", then the center hole in the 9" pan is about 2.5"); it also assumes that the walls of both pans are vertical, not tapered, so that the diameter of the pan and the center hole are constant from bottom to top. Despite these assumptions, you should be safe if you make 75% more batter - you might end up with a little left over (or be a little short), but not by much.
4 months ago Michael Fistel Sr
Calculate the area then times it by the depth, correct?
4 months ago Michael Fistel Sr
Where does depth of a pan come into the area calculations? How do you figure that in?
4 months ago Don Brabston
To determine the amount of a recipe to make in order to fit into a different pan from the original recipe's pan, you need to do a volume-to-volume comparison. To calculate the volume of a pan with a constant cross-section independent of the vertical position, just multiply the area of the cross-section by the pan's depth. (If the pan's cross-section does not have a constant area, for example a tapering pan, a simple multiplication by the depth won't work.) note that different pan depths will affect the cooking times.
5 months ago radhaks
Hi, have a recipe calling for 3 6" round cake tins (assuming at usual 2 or 3" depth) for layered cake. I want to fit batter into a jelly roll pan (half baking sheet?) with a 3/4" height. Will a single recipe fit (given the lesser height in baking sheet)?
5 months ago Sally
The batter will definitely fit- the volume for your recipe is about 60 cubic in, and for the jelly roll pan, it's about 80.
5 months ago Don Brabston
I don't think so - not even close. As Sally says, the volume of one of your 6" round cake tins (6" diameter = 3" radius) is about 60 cubic inches (assuming a depth of 2"). So, your recipe, which fills 3 of the round cake tins, will fill about 180 cubic inches. Assuming your jelly roll pan (about half a standard 13" x 18" baking sheet) is filled to a depth of 3/4", it has a volume of about 90 cubic inches. So your recipe will fill two of these jelly roll pans. (And, if the recipe fills your round cake tins to a depth of 3" instead of 2", it will fill 3 of the jelly roll tins.)
5 months ago radhaks
Thank you for the response!
5 months ago Nimrah Salim
Wish I'd seen this before! Baked a cake for 9 inch square pan in an 8 inch square pan because you know what difference could an inch make. It rose so high from the middle and I couldn't even cut of the top to make it even because it was topped with a nice crumble. Lol not the best look for the potluck but tasted fine! Thanks for this article!
6 months ago Julie Griffith
I wish that this discussed pie plate conversions too because it's not quite as simple as cake pan conversions.
6 months ago Sally
So, I actually don't have a problem with converting anything. I have a dacquoise recipe that calls for 2 12x8 jelly roll pans, but the only ones I have are 12x16. Is there any disadvantage to using the big pan?
7 months ago Lynn Spann Bowditch
If converting a recipe for a round cake pan to loaf pans, assuming the volume is calculated correctly, and I bake it until it's done correctly, does changing the shape this way affect the texture of the finished product?
9 months ago Grazi
I'm curious, if I'm converting a cake recipe normally intended for 8-inch round pans to mini pans, should i also lower the temperature, as the overall density of the batter is also less? I've always winged this and just lowered the temp by about 25 degrees F and watched it for doneness.
10 months ago Karen Jacobs
Hi, can I ask with increasing from an 8" to a 12" round cake (making a victoria sponge cake in a 12" loose bottomed tin so I will need to use my cake cutter do divide it into 2 before putting jam/buttercream in) With 2.26 should I double the recipe, times by 2.5 or triple it?
Yours a math-o-phobe with a headache! x
10 months ago Don Brabston
As I understand your question, you want to go from an 8" circular pan to a 12" circular pan. In that case, you'll need to increase the batter by a factor of 2.25/ (You could make it a factor of 2.5 to be safe, but 2.25 is the correct factor.) So, if for example, the recipe calls for 4 cups of flour, you'll need to use 9 cups instead. Let us know how it turns out, and if you have any jam/buttercream left over, send it my way ...
11 months ago Samantha Vimes
Or you could check on your thin brownies sooner.
11 months ago Luisa Carvalho
Hello I have a recipe for a 6" cake pan, but I need to make 2 cakes, one in 10" and another in 12" cake pans, do I need to make 3,5 and 4 times the recipe for this two pans??
Thank you so much for your help.....
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