Sheet Cake Sizes (Full, Half & Quarter) & Feeding Capacity

Mary and Brenda Maher

By Brenda & Mary

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sheet cake sizes

I’ve seen thousands of cake trends come and go on social media, yet sheet cakes remain a crowd-pleaser. Even inexperienced bakers could whip up a beautiful sheet cake with minimal effort, not to mention their amazing tastes when topped with the right fillings and frostings!

Are you planning to bring these lovely treats to your parties or gatherings? Then, before baking, figuring out how many people a sheet cake feeds is a must. Keep scrolling through my guide for more!

The Three Common Sheet Cake Sizes:

A full-sheet cake (18 x 24 inches, requiring approximately 16 cups of batter) serves up to 80 people. Meanwhile, 1/2 sheet cake (18 x 12 inches and using 7 to 8 cups of batter) should be enough for 36-48 guests. And the smallest option, 1/4 sheet cake (9 x 13 inches, up to 4 cups of batter), can feed 20-24 people.

Like other cake types, sheet cakes come in different sizes for different tastes and guest counts. I’ve experimented with various sizes just to learn that these three are definitely all-time favorites:

Sheet TypeSize (Inch)Cup CapacityServingsOccasions
Full-Sheet Cake18″ x 24″16 cups70-80 peopleBig events, large parties, and weddings
Half-Sheet Cake 18″ x 12″7 to 8 cups36-48 peopleSmaller events, such as receptions or birthday parties
Quarter-Sheet Cake9″ x 13″up to 4 cups20-24 peopleFamily get-togethers or baby showers
Full-Sheet Cake
Full-Sheet Cake

Cake Pan Sizes

Baking sheet cakes is already a very straightforward process; there is no need to screw things up by grabbing the wrong pan size! To sum it up, you simply need to find a pan that matches the dimensions of your chosen sheet cake.

  • Full-sheet cake size: Use 18’’ x 24’’ pans.
  • 1/2 sheet cake size: 18’’ x 12’’ pans
  • 1/4 sheet cake size: 9’’ x 12’’ (or 9’’ x 13’’) pans
Cake Pan Sizes
Cake Pan Sizes

Although most kitchen equipment stores get the gist of quarter-, half-, and full-size pans, you should describe the pan you are looking for in inches to avoid any mix-ups.

Width and length aside, do not forget to consider the depth of your baking pan:

  • Do you mostly make single-layer cakes? Then, I highly recommend deeper pans.
  • For multiple-layered cakes, there are two options. You can either use 2 shallow pans for 2 thinner cakes or 1 deep pan for 1 tall cake, which you can slice into layers later after it cools down.

Still want to increase the cake height? Then there are a few better solutions than sheet pan extenders. They prevent overbaking issues while still forming perfect straight edges! 

Serving Counts

  • Full-sheet cakes, as mentioned, are the crowd’s favorites for large events, serving about 70-80 on average.
  • As the go-to choice for smaller gatherings, half-sheet cakes can feed 36-48 people.
  • Quarter-sheet or ¼-sheet cakes are more than enough for family occasions, small parties, intimate gatherings, etc., yielding 20-24 portions.

Note that the size/ depth of each slice is still entirely up to you, so the serving counts above are mostly for reference. To be sure, you should determine the slice size first (e.g., is it 2×2 or 2×3?), then use the simple formula below to calculate how many people the entire cake can feed:

Pan Area / Cake Serving Area = Number of People

In which:

  • Pan Area = Pan Width x Pan Length
  • Cake Serving Area = Cake Width x Cake Length

Still confused? Let’s look into this example: 

Let’s say your pan is 18 x 26 inches. Multiply these two numbers (the length and width of the pan) to calculate your pan area.

Pan Area = 18 x 26 = 468

Each cake slice measures 2 x 3 inches. Multiplying 2 by 3 will help you determine your cake serving area:

Cake Serving Area = 2 x 3 = 6

Now that you know both the pan area and cake serving area, reaching an accurate guest estimation should be a piece of cake (literally!)

468: 6 = 78 people

Required Batter

Similar to serving counts, I can only give you a rough estimate of the amount of batter required because, honestly, I often use more or less depending on my customers’ requests. Feel free to adjust based on your desired cake thickness and other preferences: 

  • Full-sheet cake: 14-16 batter cups
  • ½-sheet cake: 7-8 cups
  • ¼-sheet cake: 3-4 cups

Does The Shape Of The Sheet Cake Also Affect The Number of Servings?

In the past, when customers visited my bakery and asked for a “sheet cake,” they mostly meant those square or rectangular ones baked in large, flat pans. But time has changed, and it can now cover all sorts of shapes, even round ones!

Compared to traditional square/rectangular sheet cakes, it is admittedly more difficult to cut a round one into generous numbers of slices. And guess what? Some of you may end up with larger outer or smaller centerpieces, making it all the more difficult to ensure everyone gets a fair treat. 

Let’s assume each slice is about 1.5 x 2 inches (slightly larger for midsize parties and a bit smaller for weddings). My estimation for the cake’s total servings is as follows:

For Round Cakes

Pan Size and ShapeWedding Servings Party Servings 
4″ Round42
6″ Round128
7″ Round2212
8″ Round2415
9″ Round3222
10″ Round3830
12″ Round5645
14″ Round7865
16″ Round10090

For Square Cakes

Pan Size and ShapeWedding ServingsParty Servings
6″ Square1812
8″ Square3224
10″ Square5035
12″ Square7250
14″ Square9880
16″ Square12890

Extra Factors to Consider For The Number of Servings

My sheet cake guide is not cut-and-paste for all real-life circumstances. Long story short, you must carefully assess the vibe of the party or event and your guests’ preferences to satisfy everyone while not wasting your precious batter: 

  • I did mention that a full sheet cake is meant for 70 to 80 people. However, suppose your party has only about 50 people, but all of them are huge fans of desserts; you should still opt for the full sheet then.
  • What if it is a kindergarten party, where most kids only munch on a small corner of the cakes and leave their frosting behind? Believe me, even with 100 children, half-sheet cakes should be more than enough.
  • At formal events or black-tie, fancy dinner parties, chances are people do not even touch the desserts at all. So be smart with your time and money and make small batches of ¼ sheet cakes only.

Can You Convert A Layer Cake Into A Sheet Cake?

While it is admittedly a little challenging, you can still convert a layer cake into a sheet cake. After all, layer cakes usually involve numerous ingredients and flavors, so you must be more careful when shaping them into simpler sheet cake versions.

Read and follow these steps:

Step 1.

Just stick to the original recipe while preparing your toppings, buttercream, cake batter, etc.; fortunately, there are not too many changes in their measurements! The batter should transfer from your round pan to the rectangular pan easily.

Likewise, it only takes 3 frosting cups to spread over the sheet cake while still having room for extra piping. Even if there might be some leftovers, you can use those remaining toppings for many desserts and snacks afterward anyway, so no worries.

Step 2.

Set your oven at the recommended temperature, but this time, bake 10 minutes longer than the recipe. Let’s say the instructions call for a cooking time of 30 minutes; then, your sheet cake must stay in the oven for 40 minutes or more. 

Why do I tell you so? A sheet cake (commonly rectangular) has a much larger surface area than a layer cake, meaning the oven heat will take longer to reach and cook the center evenly. An extra 10 minutes ensures your sheet cake is thoroughly baked!

While at it, do not just abandon your oven for the entire period. Not all ovens and bakes work similarly, after all, so remember to double-check your cake every 5-7 minutes.

Step 3.

Frost the sheet cake with some buttercream, sprinkling some crumble mixture atop if there are any. And feel free to drizzle some extra sauce that goes well with these heavy frosting layers, such as ganache or caramel. Just remember not to overdo it to keep the flavors balanced.

Some Tips for Cutting Your Sheet Cakes

  • Here is my secret: Chill the sheet cake for 30 minutes, and you will find it much easier to slice your cake into clean portions. No more messy crumbs and frosting disasters! 
  • A long, sharp chef’s knife with a smooth blade is the recipe for clean cuts. Just make sure it is warm to avoid tearing the cake. I usually dip the knife in hot water and wipe its blade clean after each cut. 
  • Use a knife (or a ruler/toothpick if you prefer) to mark light lines on the top of the cake. That way, you will know for sure where to cut the slices to ensure even portions. If there are any uneven cream parts on the cake’s surface, chop them off with a serrated knife.
  • Cut straight down through the cake with gentle sawing motions; do not tilt your knife or leave any leftovers around the edges. 

What To Do If You Overestimate The Guest Count for Your Sheet Cakes

Don’t let your leftover cakes go to waste in the trash. With some creativity, you can totally turn these untouched slices into something fresh and delicious, either for the ongoing party or to enjoy later! 

  • Cake pops: Crumble the slices, then combine them with cheese frosting or buttercream. Squeeze until they become squishy and shape them into small balls. Lock your cake pops with melted chocolate or candy melt coating!
  • French toast: Coat the cake slices with egg batter, then keep griddling until their edges are toasty.
  • DIY ice cream: Fold the crumbs into soft ice cream – that’s it! Another alternative is to sprinkle those crumbles atop a scoop, then dig in!

Conclusion

Despite their relatively simple recipes, there is much to discover about sheet cakes, especially if you have just stepped into the baking realm for the first time. My guide can hopefully help you navigate some of the most confusing aspects to keep every party fun and fulfilling. If you still need help, just write to me


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Mary and Brenda Maher

Mary & Brenda Maher

Mary & Brenda Maher, are the founders of Cake Girls, a Chicago-based online baking shop specializing in cake supplies, party decor, and DIY cake tutorials. They are known for their elaborate and artistic cake creations, which have been featured on the Food Network Challenge and in a reality show, Amazing Wedding Cakes.

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