How many people does a half sheet cake feed?
A one-layer half sheet cake (12 × 18 in, about 2 in tall) feeds about 36 people with party-size slices, or 49 with thin wedding slices. Two layers tall, it would serve twice that.
How to work it out
- 12 × 18 in half sheet 72 × ½ = 36 servings (party slices, Wilton chart)
- Batter: 16 cups ÷ about 4 cups per box of mix = 4 boxes
A half sheet is the cake people order for an office party, a graduation or a big birthday. The answer to “how many does it feed” depends on two things bakeries rarely mention: how tall it is and how big you cut it.
Adjust for your project
- With the other slice size
- 49 servings
- Batter to bake it (approx.)
- 16 cups
- Boxes of cake mix (at 4 cups of batter each)
- 4 boxes
By cake or tier
| Cake or tier | Party servings | Batter |
|---|---|---|
| 12 × 18 in half sheet | 36 | 16 cups |
- Wilton’s chart is for cakes about 4 in tall. A single 2 in layer — how most sheet cakes are sold — gives half the servings.
Servings by slice size and height (cakes as above)
| Slice size | Servings | Batter to bake it (approx.) | Boxes of cake mix (at 4 cups of batter each) |
|---|---|---|---|
| Party slices | 36 servings | 16 cups | 4 boxes |
| Wedding slices | 49 servings | 16 cups | 4 boxes |
One layer or two?
Wilton’s chart gives a 12 × 18 in sheet 72 party servings or 98 wedding servings — but for a cake 4 in tall, built from two 2 in layers. Most bakery and grocery half sheets are a single layer about 2 in tall, and Wilton’s own rule is that a cake under 3 in gives half the servings: 36 party slices or 49 wedding slices. Iowa State Extension’s figure for a half sheet, 24 to 50 servings, fits the single-layer cake.
| Half sheet (12 × 18 in) | Party slices (1½ × 2 in) | Wedding slices (1 × 2 in) |
|---|---|---|
| One layer, about 2 in tall | 36 | 49 |
| Two layers, about 4 in tall | 72 | 98 |
This site uses Wilton’s 12 × 18 in pan for a half sheet. Bakeries sometimes call slightly different sizes a half sheet — 11 × 15 in for some grocery-store cakes, and Iowa State’s guide lists 13 × 18 in. An 11 × 15 in single layer gives about 27 party slices by the same chart. Ask the bakery for the pan size and the height before you count.
Cutting a half sheet
Wilton’s method for sheet cakes: start 2 in from the edge, cut a line across, then slice that strip into 1½ to 2 in pieces, and repeat. For 36 party slices from a 12 × 18 in cake, that is six rows of six 2 × 3 in pieces; for more servings, cut 2 × 2 in squares and get 54. Smaller squares are fine when there is also ice cream or cupcakes.
Feeding fifty? How many cupcakes for 50 people can make up the difference, and how many people does a 9x13 cake feed covers the home-baked version. Plates for the same crowd: how many plates for 50 people.
Different size? Use the full Cake Serving Calculator.
What you’ll need
- Sheet cake pan (12 × 18 in)Mid-range price
A 12 × 18 in pan, 2 in deep, bakes a half-sheet cake for a big birthday or office party.
See options on Amazon (opens in a new tab) - Heavy-duty paper plates (bulk)Budget price
Sturdy plates that do not fold under a scoop of baked beans. Get small ones too for dessert.
See options on Amazon (opens in a new tab)
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Frequently asked questions
How many people does a two-layer half sheet cake feed?
About 72 party slices, or 98 wedding slices.
How many people does an 11 × 15 sheet cake feed?
About 27 party slices as a single layer, or 37 wedding slices.
How many people do two half sheet cakes feed?
About 72 party slices as single layers.
Other common sizes
- How many people does a 9x13 cake feed — about 18 (one layer, party slices)
- How many servings in an 8 inch round cake — 20 party or 24 wedding servings
- How many servings in a 2 tier cake — 50 wedding servings (6 + 10 in rounds)
Sources
- Wilton — Cake baking and serving guide (opens in a new tab) — Party (about 1½ × 2 in) and wedding (about 1 × 2 in) servings for 4 in high cakes by pan shape and size; 3–6 in high cakes give the same servings, under 3 in half; batter per layer.
- Wilton — Wedding cake guide (opens in a new tab) — Wedding servings for 2-layer tiers; an average 2-layer cake mix yields 4 to 5½ cups of batter; fill pans ½ to ⅔ full.
- Wilton — How to cut a round cake (opens in a new tab) — Cut a circle 2 in in from the edge, slice the ring into about 1½ in pieces, repeat, and cut the 6 in center into 12 wedges.
- Iowa State University Extension (AnswerLine) — Graduation party tips (opens in a new tab) — A half sheet cake serves 24–50 and a full sheet (18 × 26 in) 48–100, depending on 2 × 3 in or 2 × 2 in pieces. (Iowa State’s guide gives the half sheet as 13 × 18 in; this site uses Wilton’s 12 × 18 in half-sheet pan.)