Direct answer
A 1 kg cake feeds about 10–12 people comfortably with a normal-size slice. For 20 guests we usually recommend 2 kg. If the cake is one of several desserts, 1.5 kg is enough. We will tell you honestly if a size feels off.
The math here is simple, but a lot of vendors fudge it. A 1 kg buttercream cake cut into normal celebration-size slices gives you 10 to 12 servings. Cut smaller, 14. Cut for a buffet where everyone has many other dessert options, 18. Cut for a room of grown adults who love cake, 8.
We size to your room, not to your number. Tell us whether the cake is the centrepiece or one of three desserts. Tell us whether the guests are mostly children, mostly seniors, or a mix. We will quote the right size.
For a wedding, the rule is different. Plan for one slice per guest plus a 10% buffer. That is the slice they keep for the photographs, the slice they bring home for someone who could not come, the slice the photographer asks for. For a 100-person wedding, that is a 12 kg cake.
Birthdays are where most people over-order. A 1.5 kg cake is usually right for a 20-person party that also has snacks. Anything more is leftover the next morning. We do not see this as a feature.
Questions on this
Will 1 kg feed 15 people if I cut small?
Yes, comfortably. We can talk you through how to cut for the room when you order.
What about tiered cakes?
A 3 kg two-tier cake usually feeds 30 to 35 normal slices. A 4 kg three-tier feeds 50 to 60.
Got an actual cake to order?
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