Cake serving calculator

Cake servings are not guesses: Wilton, the cake-decorating brand, publishes serving charts that most bakers use. They assume a cake about 4 inches tall — two 2 in layers with filling — and two slice sizes. A party serving is about 1½ × 2 in; a wedding serving is about 1 × 2 in, the thin slice cut at a reception after dinner.

Wilton cake serving chart (4 in tall)

How the servings are worked out

servings = Σ (Wilton servings for each pan × how many) × height factor
height factor = 1 for cakes 3–6 in tall, ½ under 3 in
batter = cups per layer × layers

The height factor matters more than people expect. A bakery “half sheet cake” is usually one 2 in layer — and Wilton’s rule is that a cake under 3 in tall gives half the chart’s servings. That is why Iowa State Extension puts a half sheet at 24 to 50 servings, not Wilton’s 72 to 98 for a two-layer one.

Worked examples

• How many people does a half sheet cake feed — and why the bakery’s answer differs from Wilton’s chart.
• How many people does a 9x13 cake feed — the home baker’s sheet cake.
• How many servings in an 8 inch round cake — party and wedding slices.
• How many servings in a 2 tier cake — a 6 and 10 in wedding cake.

Tips for cutting more servings

• Cut rounds in rings, not wedges. Wilton’s method — a circle 2 in in from the edge, then 1½ in slices around it — gets the chart’s servings; wedges from the middle do not.
• Use a long, thin knife dipped in hot water and wiped between cuts.
• Decide the slice before the party. A wedding cake cut into party slices serves about a quarter fewer people.
• Add a kitchen cake. A plain sheet cake cut in the kitchen makes up any shortfall at a fraction of the price of another tier.