Half Sheet Cake Size

A half sheet cake is the classic cake for office parties, graduations and big birthdays — but bakeries and pan makers don’t all mean the same size. This guide explains the common dimensions, how many people each size serves with different slice sizes, and how much batter and frosting to plan for, with printable cutting guides.

What’s in the pack

• Printable cutting guides for quarter, half and full sheet cakes at 1 × 2, 2 × 2 and 2 × 3 inch slices
• Servings chart for sheet, round and square cakes
• Bakery order form with size, flavour, filling and message
• Party cake planner: guests, slices and cost per serving
• Baking and decorating timeline checklist

Cutting guides print at a scale that fits on US Letter or A4; lay a ruler along the edge to mark your cuts.

Sheet cake sizes

Commercial half sheet pans measure about 13 × 18 inches on the outside, so the cake itself is slightly smaller. Many supermarket bakeries sell a “half sheet” around 11 × 15 inches instead, so always ask for the actual dimensions and the number of servings the bakery quotes.

How many people does a half sheet cake feed?

Using the full 13 × 18 inch size and 2-inch-deep cake, a half sheet gives about 54 party slices of 2 × 2 inches, 36 generous 2 × 3 inch slices or 117 small 1 × 2 inch wedding-style slices. A bakery half sheet of about 11 × 15 inches gives about 35 party slices or 25 generous ones. Plan on the slice size your crowd expects: office parties with other desserts often use 2 × 2, while a cake as the only dessert calls for bigger pieces.

Worked example

A school is feeding 40 people at a graduation party. In the calculator, a half sheet (13 × 18 in, 2 in high) with 2 × 2 in slices gives 54 servings — enough, with a few spare. Switching to generous 2 × 3 in slices drops that to 36, which would be short, so they keep 2 × 2. The estimate suggests about 18 cups of batter and 6.2 cups of frosting for a ¼-inch coat, and the cutting guide shows 9 columns by 6 rows.

Baking a half sheet at home

• Check that a half sheet pan fits your oven — many home ovens take a 13 × 18 pan, but not always with room for air to flow.
• Use a pan at least 2 inches deep for a layer cake; standard rimmed baking sheets are only about 1 inch deep.
• Heating cores or flower nails in the centre help large cakes bake evenly.
• Lower the oven temperature slightly and extend the time for large pans, following your recipe’s guidance.
• Level the top with a serrated knife before frosting.

Cutting tips

• Chill the frosted cake for easier, cleaner cuts.
• Use a long, thin knife dipped in hot water and wiped between cuts.
• Score the lines lightly first using a ruler or the printed guide.
• Cut all the long lines, then the short ones.
• Serve with a cake server or offset spatula.

AI-assisted content

This guide and the templates were drafted with AI assistance and reviewed by Kedop. Servings are calculated from dimensions; bakeries may quote different numbers for their own cake sizes.