Cake Size Calculator

How much cake should you buy? Enter your guest count to find the right round, square, or rectangular cake size, with party and wedding serving estimates.

Your inputs stay in your browser. Entries are never uploaded.

Enter a whole number from 1 to 1,000.
Serving size

Party is the practical default. Smaller event/wedding slices serve more people.

Cake shape
Advanced options

This is your planning buffer, not a recommendation from the serving chart.

How the cake size calculator works

The calculator multiplies your guest count by the optional buffer, rounds up to a whole target serving, and looks for a matching cake or simple cake combination in Wilton’s published table. It does not estimate servings from surface area. For larger groups, it compares multi-cake options instead of suggesting an impractically large single cake.

Cake servings by size and shape

Round and square cakes of the same width do not always provide the same number of servings. These popular sizes show why cake shape and slice style both matter. The estimates below are for cakes 3 to 6 inches high.

Popular round and square cake serving estimates from Wilton
Cake sizeShapeParty servingsWedding servings
6 inchRound1212
8 inchRound2024
10 inchRound2838
12 inchRound4056
8 inchSquare2032
10 inchSquare3050
12 inchSquare4872

Sources & assumptions

Serving counts come from Wilton’s Ultimate Cake Serving Chart, checked August 16, 2026. Wilton’s party figures use slices about 1½ × 2 inches; wedding figures use slices about 1 × 2 inches. The chart is based on cakes 3 to 6 inches high; cakes shorter than 3 inches yield half as many listed servings.

All counts are estimates and depend on the person cutting the cake. Rectangles are shown by explicit pan dimensions—7 × 11, 9 × 13, 11 × 15, and 12 × 18 inches—rather than nonstandard “quarter,” “half,” or “full sheet” names. The optional extra percentage is chosen by you. Wilton does not endorse or sponsor One Job Tools.

Frequently Asked Questions

Wilton estimates 20 party servings or 24 smaller wedding servings from an 8-inch round cake that is 3 to 6 inches high.

Wilton estimates a 10-inch round cake provides 28 party servings or 38 smaller wedding servings; a 10-inch square provides 30 or 50 respectively.

For party-size servings, Wilton's chart indicates that one 14-inch round or one 14-inch square provides about 63 servings. For smaller wedding servings, one 10-inch square provides about 50 servings.

For 100 party-size servings, use a combination of cakes from the serving chart. For smaller wedding servings, one 16-inch round provides about 100 servings, while other shapes may require a combination.

Yes. Wilton bases party estimates on approximately 1.5 by 2-inch slices and wedding estimates on approximately 1 by 2-inch slices.

That is a planning choice, not a serving-chart rule. A buffer may help with uncertain attendance, uneven cutting, or leftovers.

Wilton says cakes 3 to 6 inches high yield the same listed servings because they use the same cutting pattern. Cakes under 3 inches high yield half the listed servings.

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