Cake Size Chart & Cutting Guide

How to cut a round cake

There are two good ways to cut a round cake, and the right one depends on size. For a small 6, 8, or 9 inch cake, cut classic wedges: slice from the center outward like a pie, dividing 360° by your number of guests to get each wedge's angle. For a 10 inch cake or larger, wedges get unwieldy, so bakeries switch to a grid — cut parallel lines about 2 inches apart across the whole cake, then cut again at a right angle to make even square servings. For very large rounds, cut a smaller circle a few inches inside the rim first, slice the outer ring into strips, then cut the inner circle into wedges. The calculator above shows the wedge size and angle for any round cake and guest count.

Cake size chart: round cake sizes and servings

This cake size chart shows how many people each standard round cake feeds. Numbers depend on how big you cut each slice, so we list three common slice sizes: party (2 × 2 in), event (2 × 1.5 in), and wedding (1 × 2 in). Assumes a single layer roughly 2 inches tall; a taller or torted cake goes further.

How many does an 8 inch cake feed?

An 8 inch round cake feeds about 12 people with generous 2×2 inch party slices, around 16 at 2×1.5 inch event slices, and up to 24 people at thin 1×2 inch wedding slices.

How many does a 10 inch cake serve?

A 10 inch round cake serves about 19 people at 2×2 inch party slices, roughly 26 at event slices, and up to 38 people at 1×2 inch wedding slices — noticeably more than an 8 inch cake because area grows with the square of the diameter.

How to cut a sheet cake (the grid method)

The secret to cutting a sheet cake evenly is to treat it as a grid instead of eyeballing wedges. Decide how big each slice should be, divide the cake's length and width by that size to get your number of columns and rows, then cut straight lines all the way across in both directions. The calculator above does that math for you — just enter your guest count.

Cake servings chart (sheet cakes)

How many cake servings you get comes down to two things: the cake's total area and how big you cut each slice. The round cake size chart above covers round cakes; this cake servings chart covers the three common U.S. sheet cake sizes. Depth is assumed to be a single 2-inch layer; a taller torted cake can stretch these numbers.

Standard cake slice sizes

Cake serving sizes are more about the occasion than the cake:

Party slice — 2 × 2 inches

The everyday birthday and celebration size. Generous, easy to plate, and the default most people picture.

Event slice — 2 × 1.5 inches

A common catering compromise that stretches a cake further without feeling stingy — good for showers, office parties, and buffets.

Wedding slice — 2 × 1 inch

The traditional formal serving. Because tiered wedding cakes are usually 4 inches tall, a 1×2 inch footprint still yields a satisfying sliver of cake.

Round & square cakes

Round cakes are trickier because wedges get impractically large as guest counts climb. For big crowds, bakeries often cut round cakes in a grid too — a series of parallel lines rather than pizza slices. This calculator shows classic wedges for round cakes so the result stays intuitive, and a clean grid for square and sheet cakes. Square cakes serve more people than round cakes of the same width because there are no rounded corners to lose.

5 tips for clean cake slices

Use a tall, thin knife. A long serrated blade for the crumb and a thin slicing knife for the interior both work well.

Warm the blade. Dip the knife in hot water and wipe it dry between cuts — heat glides through buttercream and frosting.

Wipe every slice. A clean blade stops crumbs and filling from smearing down the next cut.

Cut straight down. Press down rather than dragging back and forth to keep layers from sliding.

Mark first, cut second. Score the grid lightly across the top before committing so every slice matches.