How to use this calculator
Count guests who want cake and choose portions per guest. Use the bakery’s serving yield for the exact cake height, shape and cutting style you intend to order. Enter a decimal such as 0.75 if you expect only three quarters of your guests to take a serving.
The formula and assumptions
Guests × portions per guest → Divide by servings per cake → Round up to whole cakes
Cakes = ceiling(guests × portions per guest ÷ servings per cake). This is a serving-count calculator, not a cake-diameter chart. It assumes all cakes have the same serving yield and price. Unused servings come from rounding to whole cakes.
Worked example
For 30 guests at 1 portion each, you need 30 portions. If one cake provides 24 servings, 30 ÷ 24 = 1.25, which rounds up to 2 cakes. That provides 48 servings, leaving 18 spare. At 35 per cake, the cost is 70.
Before you order
Ask whether the quoted yield uses small event portions or larger dessert portions. If the rounded result leaves too much cake, compare a larger cake or a mix of different sizes with your baker. Decorations, delivery and dietary alternatives may cost extra.
Frequently asked questions
What size cake serves 30 people?
There is no single answer without cake height and portion size. Ask your bakery for a cake with at least 30 servings, or enter the yield of the cake you are considering.
Can I use this for cupcakes?
Yes. Enter the number of cupcakes in one purchasable box as servings per cake, and the box price as price per cake.
Why are there spare servings?
You can order only whole cakes in this model, so the result rounds up.
Planning estimates only. Adjust portions for your guests, menu and event. Confirm serving yields, prices and venue capacity with your suppliers.