How many people does an 8-inch round cake serve?

An 8-inch round cake typically serves 12 people when cut into 2 layers (the standard for most celebration cakes). A single-layer 8-inch round serves about 12 modest slices, while a 3-layer version can stretch to 28 servings when cut into smaller party-sized pieces.

What is a standard cake serving size?

A standard dessert serving is roughly 1.5 to 2 inches wide by 2 inches tall by 4 inches deep — about the size of a small rectangular slice. Wedding cakes are typically cut into smaller 1-inch wide slices to extend servings, while birthday and celebration cakes use the larger 2-inch cut.

How many calories are in a slice of cake?

Calories per cake slice vary widely. A slice of vanilla layer cake with buttercream is around 350–450 kcal. Chocolate fudge cake runs 400–480 kcal. Angel food cake is much lighter at 150–180 kcal per slice. Cheesecake averages 350–450 kcal. Frosting and fillings account for 30–50% of total calories, so a "naked" cake has significantly fewer calories.

How many servings does a full sheet cake yield?

A full sheet cake (18 x 24 inches) yields approximately 54 generous servings or up to 108 smaller party-sized pieces. A half sheet (11 x 15 inches) serves 24–48 people, and a quarter sheet (9 x 13 inches) serves 12–24. Sheet cakes are the most economical choice for large groups.

Does number of cake layers affect servings?

Yes — more layers mean more height, which allows each serving to be taller and narrower without reducing the perceived portion size. A 3-layer 8-inch round cake can serve nearly twice as many people as a single-layer 8-inch round. Most bakeries use 2 layers as the standard for celebration cakes.

How do I calculate servings for an oddly shaped cake?

For non-standard shapes, calculate the total volume in cubic inches (length x width x height for rectangular areas), then divide by 8 cubic inches — a common standard serving volume (2" x 2" x 2"). For tiered cakes, calculate each tier separately and add the totals together.

Cake Serving Size Chart — How Many Slices Per Cake? (2026)

Size	Servings	Total kcal
6"	12	4,680
8"	20	7,800
9"	24	9,360
10"	30	11,700
12"	40	15,600
14"	60	23,400

How Many Servings Does a Cake Yield?

Knowing how many slices a cake will yield is one of the most practical questions in baking — whether you are planning a birthday party, wedding, or just a casual dessert. The answer depends on three things: the shape of your cake, the size (diameter or pan dimensions), and the number of layers. A 2-layer 8-inch round cake is the most common celebration cake and yields about 20 servings — enough for a modest birthday party.

Standard Serving Size

A standard dessert serving is approximately 2 inches wide, 4 inches deep, and 4 inches tall for a layered cake. Wedding cakes use a narrower 1-inch wide cut to maximize servings. Sheet cakes are typically cut into 2 x 2 inch squares. This calculator uses the dessert-portion standard unless otherwise noted.

Round vs Square vs Sheet Cakes

Round cakes are the most popular choice for birthdays and celebrations. They are elegant and easy to portion, but a round pan wastes some volume compared to a square pan of the same diameter — which is why square cakes of the same dimension yield about 25-35% more servings.

Square cakes maximize servings per inch of pan because there are no curved edges — every cut produces a full rectangular slice. A 12-inch square cake with 2 layers can serve up to 72 people, making it a great choice for larger gatherings.

Sheet cakes are the ultimate crowd-pleaser. A full sheet cake (18 x 24 inches) serves 54 or more people and is far easier to transport and cut than a tiered cake. Half and quarter sheets are standard at most grocery store bakeries. Sheet cakes are typically single-layer, though some bakeries offer a 2-layer "double sheet" for larger events.

How Layers Affect Servings

Adding layers is the smartest way to serve more people without buying a larger pan. A 3-layer cake allows you to cut thinner, narrower slices that still look impressive because of their height. For example, a 2-layer 10-inch round yields about 30 servings, while a 3-layer version of the same diameter can serve 40. When budget matters, go taller — not wider.

Cake Calories: What to Know

Cake calories vary dramatically depending on the recipe and frosting. Angel food cake is the lightest option at around 160 kcal per slice, owing to its fat-free sponge base. Dense, frosted layer cakes like chocolate fudge or carrot cake average 400–440 kcal per standard serving. Cheesecake falls in the same range at roughly 400 kcal, despite having no traditional cake layers — its density makes up the difference. If you are tracking calories, consider a thinner slice or a lighter cake type. The Caloria app makes it easy to log cake and other celebration foods without derailing your nutrition goals.

Quick-Reference Serving Chart

Shape & Size	1 Layer	2 Layers	3 Layers
Round 6"	8	12	16
Round 8"	12	20	28
Round 9"	16	24	32
Round 10"	20	30	40
Round 12"	30	40	56
Round 14"	40	60	80
Square 6"	12	18	24
Square 8"	18	32	48
Square 9"	24	40	54
Square 10"	30	50	70
Square 12"	48	72	96
Square 14"	64	96	128
Quarter Sheet (9×13")	12	18	24
Half Sheet (11×15")	24	36	48
Full Sheet (18×24")	54	80	108

Standard dessert serving: approx. 2" wide slice. Wedding-style cuts yield more servings (use 1" width).

Cake Serving Size Chart

Layer Comparison

All Round Sizes (2 Layers)

Calories by Cake Type