### CakeWhat to CookBakingKitchen Hacks

# 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

*(n*ot only because they're gluten-free, but for an extra dimension of flavor, too).

## Comments (68)

## about 1 month ago Robyn Cormac

There is a website called cakeometer which does the scaling for you. I've just made a three tier wedding cake using it and it worked

## about 2 months ago RH

Hello,

I am not a bit ashamed about asking for help! Thanks. How should I adapt a recipe for 2 nine inch pans to fill 3 eight inch pans? I have been just increasing the measurements by 50 percent and it does make a magnificently tall cake but it is almost too tall! I tried the math but came up with something like 19 percent increase? I was thinking of rounding that to 25 percent but thought I'd check with the professor first.

Best Regards,

McJeeps

## 2 months ago Robyn Cormac

Hi

I need to scale down a 10" round pan to a 6" one. I've done the calculation (I think!), and the scale is 2.7 - but I'm not sure how to calculate 2.7 less of everything. Am probably just being dense, but could you explain it?

Many thanks!

## 3 months ago Felicia Gonzales

I want to make a 12in square cake 2in deep. Do I need to double the recipe? I am making the Hershey Chocolate Recipe.

## 3 months ago Don Brabston

which hershey chocolate recipe do you mean? please provide a link.

## 3 months ago Lim1413

hi, i am making brownies this Saturday and the recipe ask for 8x8 square pan, but I only have 12x8 inches rectangle pan(not sure if I have measure it correctly), so do I need to divide 96 inches by 64 which equals to 1.5. Does this means I need to double the recipe?

## 3 months ago Don Brabston

You did the calculation (96/64 = 1.5) correctly, but your conclusion is wrong. You need 50% more batter, not double. (For example, if the recipe calls for 2 cups of flour, you'll need 3 cups, not 4.)

## 3 months ago Lim1413

So, does this means I need to remain the same recipe or increase some by 2 , because the recipe is mostly in grams ,for example if it needs 200g all purpose flour do I need to change into 400g instead?

## 3 months ago Lim1413

Sorry for troubling, and thank you for helping, I get it now, thx a lot o∩_∩o

## 3 months ago kath

yes round cake. I have done with 6" cake and wonder how much more batter to add for bigger round cake, such as 7", 8" and 9"? shall I increase 50% or less for each pan size. all in round pans. thanks.

## 3 months ago Don Brabston

it's not quite that simple, but it works out to about a 30-35% increase for each step up in pan size. Specifically, to go from a 6" pan to a 7" pan, you'll need about 36% (roughly 1/3) more batter; to go from a 7" to an 8" pan, you'll need another increase of 30% (or 78% more batter than for a 6" pan); and to go from an 8" pan to a 9" pan, you'll need another 25% increase (or 125% more batter than for a 6" pan). (For the greatest leap from a 6" pan to a 9" pan, you'll need 2.25 times the batter; i.e., 125% more batter.)

## 3 months ago kath

Thanks for the info. Very helpful. :)

## 3 months ago kath

I have batter for 6" cakes. How to calculate batter for 7" and 8" batter as I want to bake on a bigger birthday cake? Thank you.

## 3 months ago Don Brabston

I don't fully understand your question. Are these cakes circular? If so, you will need batter for 3 (actually 3.2) 6" cakes to bill one 7" and one 8" pans to the same depth as the 6" pans.

## 3 months ago Jennifer W

Sorry if this has already been addressed (there is a lot of info here) but is it true that when increasing batter amounts that you dont necessarily increase the leavening accordingly? For example, Ive read on Rose Levy's site if you're say, tripling, that you might not triple the amount of baking powder but only double it. I am making a three tiered cake in a few weeks, the largest pan being 14" round, so Id like to know if this is something I need to worry about!:)

## 3 months ago Carol

I am making a special bundt cake assortment for my nieces wedding and I have a bundt pan that is larger than the norm. In order to get a bigger cake so I can decorate I wanted to use a larger pan (deep) which I purchased at Bed Bath and Beyond. Do I add a ratio of one and half cake mixes to a larger pan and bake longer? I think it's pretty simple..but want assurance I am on the right track. Thank you!

## 3 months ago Patty

Hi I'm making zucchini bread and I have different size pans ithen what the recipe calls for. It's 4 x 4 x 14 inch loaf pan. I'm not quite sure how long to bake it. I need your help thank you... Patty

## 3 months ago Mindy

I have a big rectangle pan which is I think 11x25 if I'm measuring correctly. I also need 6" round cake. If a recipe says it makes 3-9" layers then should I double that recipe for the amount I need? I have to make this cake today. Sorry I'm terrible at math! ?

## 3 months ago Marianne

You don't need double the amount--you'll end up with a lot leftover. You need about 1.6 times the amount, but depending on the recipe, it might just be easier to double, and make an extra 9" or other small (8" or 9" square) one. Or, you could double the recipe and make the cakes a little taller (just don't fill the pans past 2/3rds or so full), but you'd still have batter left over. You would probably be ok with 1 and a half times the recipe, but the cakes might be just a liiiiittle short.

Quick math refresher:

We're ignoring height in the calculations, since the assumption is that we want the height to be the same as the recipe.

For the rectangle, it's simply length x width. (11x25)

For the rounds, it's pi times (radius squared), with the radius being 1/2 of the measurement of the pan all the way across. Ie, the 9" pan has a 4.5 radius, and 4.5 squared is 20.25. The 6" has a 3 inch radius, which comes to 9 when squared.

The numbers:

Recipe yielding 3, 9" layers (I'm assuming 9" round) will give you = (3 x {3.1416 x 20.25}) = (3 x {63.6}) = 190.85, or 191.

You need: (11x25) + (3.14159 x 9) = 275+28.27= 303.27, or 303.

What you need vs what the recipe yields:

303/191= 1.58, or roughly 1.6.

If you doubled the original, you'd end up with 382. (191x2) You'd have 79 left over, which would be enough for an entire additional 9" square cake.

Which you can bake and send to me if you'd like ;)

## 4 months ago Cheryl Creamer Merrill

Can you bake a 7up cake in a 9x13 pan, or does it have to be baked in a bundt pan?

## 4 months ago lea smye

what wonderful info the mathematically challenged baker (aka ME) - thanks so much! sorry if i missed this explanation but what if you want to scale DOWN a recipe? i.e. a recipe that calls for two, 9 inch pans but you'd prefer to make it in 2, 7 inch pans? or is this a dumb question with an obvious answer? ;)

## 4 months ago Don Brabston

No such thing as a dumb question. If you want to keep the same depth batter in the 7" pans as in the original 9" pan recipe, you'll need only about 60% of the original batter. (The cooking time will be a bit shorter than in the original recipe, so start checking for doneness sooner than you would for the original recipe.)

## 4 months ago Maggie Asfahani

So, to be clear...I don't have to worry about depth? But less batter would fit in a 9x2 than a 9x3 pan....

## 5 months ago Gitanjali Mohan

hi, the recipe calls for 2 9 inch round pans...I only own 6 inch round pan... so how do I adjust the cooking time?

## 6 months ago cmhill87

I'd love a little more info on how to adjust cooking times. What does "a little bit longer" mean -- 2 minutes? 10 minutes? I'm making a 9x9 brownie recipe in a 9x13 pan. The recipe calls for 35 minute cook time, but I'm just unsure how long I'd need to extend that. Can anyone help? Thanks!

## 7 months ago Debbie Hargreaves

I can see all the maths but no actual 'chart' Where can I find it?

## 7 months ago Jane Grover

Hi there! Stumbled across your page and I'm so glad I did. I'm terrible at math, but love baking and cooking. Here's my question (I'm sorry if it's already been asked...I don't have the patience to sift through comments already posted!) I'd like to bake a 8 x 8 brownie recipe into a half sheet pan (mine are from webstaraunt.com) and measure 13 x 18. When I do the math...234" divided by 64" I get 3.656. Should I multiply the original recipe ingredients down to 3.5 or bump it up to 4? Maybe 3.5 times would produce too thin brownies? Thanks!

## 8 months ago Patricia

This is great information, thanks. I have a question about adjusted cooking time though. I'm converting a 9" round to a 12x18 pan. Doing the math, I'll need 3-3/8 times the batter, but I plan to round up to 3-1/2 for a slightly taller cake. What would be my estimated cooking time? I wouldn't worry too much about this if the original and new pan sizes were similar, but going from a 9" round to a huge rectangle has me worried about overcooking the edges before the middle is anywhere near done. The original recipe is 350 degrees for 20-25 minutes and a metal pan. Thanks for the help!

## 8 months ago Don Brabston

Patricia,

Looks like you've got the math right for the recipe size. As for the cooking time, I wouldn't worry about the slightly greater depth due to rounding up (only 4% deeper due to your rounding up), but I think you're right to be concerned about the edges getting overcooked before the center is done. The distance from the corners of the rectangular pan to the center is about 11", and the distance from the middle of the long side to the center is 6", whereas the distance from the rim of the circular pan to its center is only 4.5". But, assuming your cake depth is, say, 10"-12", the vertical distance to the center is 5"-6" for both pans. Solving the partial differential heat equation is beyond me these days, so I can't provide a quantitative answer, but my guess is that the vertical distance will dominate the consideration (assuming your pan is in the middle of your oven and heat gets to the cake from all sides), and the cooking times should be about the same for both the circular and rectangular pans. To be safe, you should probably start checking for doneness in the middle of the cake at around 15 minutes, I would think. Let us know how the cooking time turns out.

Don

## 8 months ago Patricia

Thanks Don. I'm going to lower the temp a little, use cake strips around the pan and cook with the convection feature of my oven (which I rarely use). Hopefully the combination of all 3 will produce and evenly baked cake. Fingers crossed. Thanks for your help and I'll let you know how it works out.

## 9 months ago Sebastian Lett

Thoughtful comments . I am thankful for the details . Does anyone know if my company might be able to acquire a blank a form copy to complete ?