Cake Serving Calculator

in
in
For rectangular pans only.
in
Typical: 1 in wedding serving; 2 in party serving.
Food

Calculate how many servings a cake will yield based on its size, shape, and serving size.

Formula

Round: servings = 2πr ÷ slice width; Rectangle: servings = (L/w) × (W/w)
  • Round cakes: divide circumference by slice width.
  • Rectangle cakes: grid division (length ÷ slice width × width ÷ slice width).
  • Standard party slice: 2 in wide; wedding slice: 1 in wide.
  • This assumes a 4-inch tall cake (standard 2-layer cake).

9-inch round cake, 2-inch slices

Inputs
  • Pan Shape: round
  • Pan Diameter / Length: 9 in
  • Pan Width (rect only): 13 in
  • Slice Width: 2 in

Circumference = 2π×4.5 ≈ 28.3 in. 28.3/2 ≈ 14 slices.

Frequently asked questions

How big is a standard cake serving?
A standard party serving is about 2 inches wide. Wedding caterers typically use 1-inch slices.
How many layers does this assume?
A standard 2-layer cake is about 4 inches tall. Taller cakes may yield more volume per slice.
What size cake for 50 people?
For 50 party servings (2-in slices), a 12-inch round or 13×9 sheet cake should work.
Should I bake extra?
Always bake at least 10% extra servings for unexpected guests.