How Much Cake Do I Need? A Simple Serving Guide (kg, lb & Inches)

Ordering a cake is the easy part. Choosing the size is where most people get stuck. Order too small and the last few guests go without. Order too big and you’re eating cake for three days.

We’re a home bakery, and “how much cake should I take?” is the question we answer most often. So we’ve put our answer in one place. Use the quick chart if you’re in a hurry. Read on if you’d like to understand how we work it out. The guide uses weight, so it works whether you’re buying from a bakery, ordering online or baking at home.

The quick answer: cake size by number of guests

These suggestions are for a normal party slice. If your number sits between two sizes, take the bigger one. A little extra cake is never a problem. A short cake always is.

The simple maths behind it

If you like to do your own sums, here is the whole method:

Number of guests × weight of one slice = total cake you need

A normal party slice weighs about 70 to 100 grams (2.5 to 3.5 oz). A smaller slice, the kind you cut after a full meal, is closer to 70 g. A generous slice, the kind kids and cake lovers prefer, is closer to 100 g.

So for 20 guests:

• At 70 g a slice, you need about 1.4 kg (3 lb)
• At 100 g a slice, you need about 2 kg (4½ lb)

That is why we usually say 1.5 to 2 kg for 20 people, depending on the party.

How many slices do you get from each size?

The weight of a cake includes the sponge, the filling and the frosting. Heavy decoration, such as extra toppings or a fondant design, adds weight but doesn’t add many extra slices. If your cake is very decorated, ask your baker how many servings to expect.

Why different websites give different answers

You may have noticed that one site says a 1 kg cake serves 8 people, another says 12, and another says 15. They aren’t all wrong. They’re just assuming different slices.

A 1 kg cake gives you about 10 generous slices or 14 small ones. Neither is the “right” answer. It depends on how big you cut and how hungry your guests are. It also depends on where you are. Wedding-style slices are small and neat, while party slices at home tend to be bigger. That is why we always ask two things before suggesting a size: how many people are coming, and what they’ll eat before the cake.

Six things that change how much cake you need

1. Will there be a meal before the cake?
If guests have just eaten, slices will be smaller and you can go one size down. If the cake is the only sweet at a tea-time party, go one size up.

2. Who is coming?
Children usually eat smaller slices, but they often come back for another one. A group of friends or a big family will usually finish the cake. At an office celebration, people tend to take small slices.

3. How rich is the cake?
A rich chocolate or caramel cake fills people up quickly, and one small slice is usually enough. Lighter flavours like pineapple, vanilla or fruit cakes often get a second slice. If you’re choosing a rich flavour, you can go slightly smaller.

4. Are there other desserts?
If you’re also serving sweets, ice cream or pudding, you can order a little less cake. If the cake is the only dessert, order a little more.

5. How will it be cut?
Cutting at home with a regular knife usually gives bigger slices than a planned, even cut. If you want to stretch your cake, cut smaller wedges from the start. We show how below.

6. Do you want leftovers?
Some families love having cake the next day. If that’s you, add a size. If not, stick to the chart.

What size is a ½ kg, 1 kg and 2 kg cake in inches?

The diameter of a cake depends on how tall it is, how many layers it has and how it’s finished, so two 1 kg cakes from two bakers can look quite different. Our cakes are about:

• ½ kg: [] inches ([] cm) across
• 1 kg: [] inches ([] cm) across
• 1.5 kg: [] inches ([] cm) across
• 2 kg: [] inches ([] cm) across

If your cake needs to fit on a particular table, in a particular fridge or in a particular box, check the size with your baker before you order.

Cake size guide for common celebrations

• Small family birthday (5 to 8 people): 1 kg (2 lb)
• Kids’ birthday party (15 to 20 children): 2 kg (4½ lb), or 1.5 kg (3 lb) plus a box of cupcakes
• Anniversary dinner for two: ½ kg (1 lb)
• Anniversary with close family (10 to 15): 1 to 1.5 kg (2 to 3 lb)
• Baby shower or engagement (25 to 40 guests): 3 to 4 kg (6½ to 9 lb)
• Office or college celebration (10 to 20 people): 1 to 2 kg (2 to 4½ lb), or a box of cupcakes
• Friends’ get-together: 1 kg (2 lb) for up to 10 people
• Festival gatherings, such as Christmas, Diwali, Eid, Easter or New Year: 1 to 2 kg (2 to 4½ lb), depending on how many relatives and friends drop in

Festival days and long weekends are busy for every baker, so order early. We explain how far ahead below.

Cake plus cupcakes or brownies: an easy way to feed more people

For bigger gatherings, many of our customers order one cake for the cutting and a box of cupcakes or brownies to share. It saves you from cutting 40 slices, and everyone gets something.

• Cupcakes: plan on 1 per person, or 1 to 2 for a hungry crowd. A box of [] serves about [] people.
• Brownies: plan on 1 to 2 pieces per person. A box of [] serves about [] people.

Example for 30 guests: a 2 kg (4½ lb) cake plus a box of [__] cupcakes.

One big cake or two smaller ones?

For 40 guests or more, you can order one large cake or two medium ones. Two cakes can be easier because:

• You can offer two flavours, for example one chocolate and one fruit.
• You can cut one while the other waits in the fridge.
• Smaller cakes are easier to carry and store.

One big cake looks great for a cutting ceremony and photos. If you’d like both, order a large cake for the cutting and a second cake to serve.

The largest single cake we bake is 10 kg. For bigger events, we suggest splitting the order, and we’ll help you plan it.

How to cut a round cake to get more slices

1. Cut the cake in half through the centre, then cut each half into quarters.
2. Cut each quarter into 2 or 3 wedges, depending on how many slices you need.
3. For a very large number of guests, cut a small circle from the centre first, then slice the outer ring. This gives more even, smaller pieces.
4. Wipe the knife clean between cuts. It keeps the frosting neat.

How far ahead should you order?

Every bakery is different, so check with yours. As a guide, regular cakes usually need a few days’ notice, and custom, theme or multi-tier cakes need a week or more. We bake every cake to order, so we ask for 24 to 48 hours for regular cakes and 48 hours or more for custom ones. For festival days and long weekends, order as early as you can.

How to store leftover cake

Leftover cake keeps best in the fridge, so put it away as soon as the party is over. Don’t leave it out on the table for hours, especially a cake with cream or fresh fruit.

• Use a closed box. Slide the cake into an airtight container, or a clean cake box with the lid on. This stops the sponge from drying out and keeps it from picking up the smell of other food in the fridge.
• Eat it within 4 days. For most cakes, 4 days is the sweet spot for taste and texture. Cakes with whipped cream are best finished within 2 to 3 days.
• Finish fruit cakes early. A cake with fresh fruit is best eaten the same day or the next, because the fruit releases moisture and the cake goes soft quickly.
• Take it out 15 minutes before serving. Cold cake tastes flatter and firmer. A short rest at room temperature softens the sponge and the cream, and brings the flavour back.

Want exact timings for every type of frosting, plus tips on freezing and refreshing a dry slice? Read our guide on how long cake is good for in the fridge.

What to tell your baker when you order

Whichever bakery you order from, send these details and you’ll get the right size the first time:

Number of guests: [ ]
Occasion: [ ]
Will the cake be served after a meal? [Yes / No]
Flavour: [ ]
Any dietary needs, such as eggless, nut-free or vegetarian: [ ]
Date and time needed: [ ]
Message on the cake: [ ]

If you’re not sure, just share your guest count and let the baker suggest a size. A good baker will be happy to.

Order a fresh, 100% eggless cake in Udupi

Every cake at Ali’s Bake is 100% eggless, baked fresh to order in our home kitchen in Udyavara, and delivered across Udupi, including Udyavara, Ambalpady, Adi Udupi, Kalsanka and Malpe. Delivery starts from ₹50 depending on distance, and you can pick up from our kitchen for free.

Browse our Classic Cakes, Premium Cakes, Dream Cakes and Cup Cakes, or read how cake delivery in Udupi works.

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Frequently asked questions

How many people does a 1 kg cake serve?
A 1 kg (2.2 lb) cake gives you about 10 generous slices or up to 14 smaller ones. For most parties we say 8 to 12 people.

How many people does a 2 lb cake serve?
A 2 lb cake is a little under 1 kg, so it serves about 8 to 12 people at a normal party slice.

Is a 1 kg cake enough for 15 people?
It’s tight. You’d need to cut small slices, and some guests may not get seconds. For 15 people we suggest 1.5 kg (3 lb).

How much cake do I need for 20 people?
Order 1.5 to 2 kg (3 to 4½ lb). Take the larger size if the cake is the main dessert, or if the group includes children or cake lovers.

How much cake do I need for 50 people?
About 4 to 5 kg (9 to 11 lb). For a big party, consider splitting it into two cakes, or a cake plus a box of cupcakes.

How many people does a ½ kg cake serve?
About 4 to 6 people, which suits a small family celebration or an anniversary for two.

Does the cake weight include the frosting?
Yes. The weight covers the sponge, filling and frosting. Heavy decorations add weight but don’t add many slices.

Should I order a bigger cake if I’m not sure?
Yes. A little extra is always better than running short. Tell your baker the guest count and ask them to suggest a size.