How to Cut a Round Cake

Co-authored by wikiHow Staff

Last Updated: July 28, 2022 References Tested

Even Triangles

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Small Squares

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Inner and Outer Sections

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Precise Cuts for Storage

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Video

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Things You'll Need

ARTICLE

VIDEO

Round cakes are tasty treats that, at times, can be difficult to cut into enough pieces to serve everyone. In addition to the typical method of cutting a round cake into triangle-like slices, round cakes can also be cut into small square pieces, smaller triangle slices, and even long, thin strips. One method was even designed by a scientist to ensure every piece of cake is fresh and moist.

Method 1

Method 1 of 4:

Even Triangles

1
Select a knife that’s big enough to cut across the entire round cake. For example, if the diameter of your round cake is 10 inches (25 cm), your knife should be at least that long. If you’re unable to find a knife as long as the diameter of your cake, choose one that’s as long as possible.^{[1]
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- If your knife isn’t as long as the diameter of your cake, you’ll need to slide the knife along the top of the cake in order to make a complete line in the frosting.
2
Soak your knife in warm water before using it to cut your cake. Fill a tall glass with warm tap water. Place your knife inside the water and lean it against the edge of the glass. Leave your knife in the water until you’re ready to cut your cake. When you’re ready to cut the cake, take the knife out of the glass and wipe the water off with a tea towel.^{[2]
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- You’ll need to make sure your glass is tall enough to hold the knife you’re using.
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3
Use your knife to score a line through the middle of the cake. Hold your knife above the cake with both hands. Hold the handle with your dominant hand and the tip of the knife with your non-dominant hand’s fingertips. Place your knife across the entire cake, going through the middle of the cake. Use a rocking motion with the knife, from the tip to the handle, to score a straight line across the cake.^{[3]
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- Press into the frosting to score the line, only until you read the first layer of cake. Do not cut into the cake itself.
4
Score a second line at a 70-degree angle to the first line. Start the second line from the middle of the first line. Move your knife so that the second line is at a 70-degree angle to the first line, which should create a piece that is about 1/3 of that half of the cake, or 1/6 of the entire cake.^{[4]
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- The first 2 lines have now divided the cake into 3 pieces.
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Created a third line through the middle of the smaller triangle. One half of your cake will look like it’s made of 2 triangles, one larger than the other. The third score line should divide that smaller triangle exactly in half, from the middle.^{[5]
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- The first 3 lines have now divided the cake into 4 pieces.
- The 2 smallest pieces will be the size of all the final pieces.
6
Score 2 more lines to divide the larger triangle into 3 pieces. The next 2 score lines will divide the larger triangle piece into 3 even sections. From a technical perspective, each of the 5 resulting triangle pieces should have an approximate 36-degree angle.^{[6]
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- This entire process is based on estimating the size of the slices, but you’re aiming to make all the pieces equal in size.
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Use your knife to extend the 4 half-lines across the cake. One half of the cake is now scored into 5 pieces. Only 1 of the lines scored so far goes across the entire diameter of the cake. Four of the lines scored so far only go halfway across the cake. Use your knife to extend those 4 half-lines so they go across the entire diameter of the cake.^{[7]
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- The final result of this process will divide the round cake into 10 even pieces.
- If you have more than 10 people to serve, you can cut each of the 10 pieces in half to produce 20 even pieces.
8
Cut your cake along each of the score lines to create 10 even pieces. Dip your knife in the warm water and wipe it off with a tea towel in-between each cut you make in the cake. Use your knife and cut through the entire cake following the score marks you’ve made. Cut from the middle point of the cake for each slice.^{[8]
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- Pull the knife out of the bottom of the cake slowly.
- Scoop up each piece of cake with an offset spatula after it’s cut, or wait to start handing out cake pieces once the entire cake is cut.

Method 2

Method 2 of 4:

Small Squares

1
Warm your knife in water before you start to cut the cake. Put your knife into a glass or container filled with warm tap water. Leave it in the container until you need it to slice the cake. Whenever you take the knife out of the water, wipe it off on a tea towel.^{[9]
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- Make sure the glass or container you use is tall enough for the knife you’ve chosen to use.
2
Slice the round cake into long, thin strips. Each strip should be about 1 in (2.5 cm) wide. Once you’ve sliced off a strip of cake, lay it flat onto a cutting board or plate. Remember to warm your knife between each large slice.^{[10]
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- If you don’t need as many pieces of cake, you can make the strips larger/wider.
3
Cut the long slice into 1 in (2.5 cm) strips. Once the longer slice is laying flat on a cutting board, use your knife to cut it into 1 in (2.5 cm) strips. The end result will be a piece of cake that’s 1 in (2.5 cm) thick and 1 in (2.5 cm) wide, with a length that’s equal to the height of the cake.^{[11]
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- You don’t need to warm the knife in water to cut these small strips.
- You can also cut the flat slice into strips longer than 1 in (2.5 cm) if you’d like.

Method 3

Method 3 of 4:

Inner and Outer Sections

1
Heat up your knife in warm water before you begin. Allow your knife to sit in a glass of warm tap water before you begin slicing the cake. Wipe the excess water off the knife with a tea towel when you take it out of the water. Re-warm the knife between each major cut in the cake.^{[12]
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- The warmed metal will cut through the cake quicker and easier than a cold knife.
2
Cut a circle in your cake, 2 inches (5.1 cm) from the edge. Slide your knife into the cake vertically in a spot that’s approximately 2 inches (5.1 cm) from the edge. Keep the knife vertical and cut a circle in the middle of the cake that stays 2 inches (5.1 cm) from the edge all the way around. Essentially, you’re creating a new round cake in the middle of your existing round cake.^{[13]
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- This method will only work for cakes that are 8 inches (20 cm) in diameter or larger. Smaller cakes should be cut into the typical triangle pieces.
- The end result will be an outer ring-shaped cake and an inner round cake.
3
Cut the ring-shaped outer cake into 1.5 in (3.8 cm) wide pieces. Re-warm and dry the knife before proceeding. Use the knife to cut the outer, ring-shaped cake into individual pieces that are about 1.5 in (3.8 cm) wide. For an 8 in (20 cm) cake, this will result in 21 pieces of the same shape and size.^{[14]
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- For cakes larger than 8 inches (20 cm), you can either keep the same slice width of 1.5 inches (3.8 cm), which will result in more than 21 pieces, or you can increase the width of each slice in order to still create about 21 pieces.
4
Slice the smaller round inner cake into triangles pieces. Once the 21 outer slices of cake have been removed, you have a new, but smaller, round cake to cut. Start but cutting the inner round cake in half, through the middle. Then cut the cake in half again, at a 90-degree angle to the first cut. Depending on the size of the inner cake and the number of slices you need, you can either cut each quarter section in half (which will give you 8 slices, or you can cut each quarter section into thirds, which will give you 12 pieces.^{[15]
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- For example, if the entire cake was 8 inches (20 cm) in diameter, you’ll have a 4 in (10 cm) mini-round cake left in the middle.
- Don’t forget to rewarm and dry your knife before you start cutting the inner cake. However, you won’t need to rewarm between cuts.

Method 4

Method 4 of 4:

Precise Cuts for Storage

1
Use this scientific method for cakes you plan to store. This method works best when you have a round cake that is not going to be eaten all at once, for example, at a party. If only a small portion of the cake is going to be eaten, and the rest is going to be stored in the fridge for later, this is the method that will provide you with the freshest cake day-after-day.^{[16]
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- This method was created by a British mathematician named Sir Francis Galton and first published in the journal Nature in 1906.
2
Make one cut across the entire cake, slightly off-centre. This first cut needs to go the entire diameter of the cake, but not down the exact middle of the cake. Instead, the cut needs to be off-centre because you’re essentially cutting a strip out of the middle of the cake. Make this first cut about 0.5 in (1.3 cm) to the right of the middle of the cake.^{[17]
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- The final piece of cake will be 1 in (2.5 cm) wide.
- If you want a larger slice of cake, cut the cake more than 0.5 in (1.3 cm) from the middle.
3
Cut the cake again, 1 in (2.5 cm) to the left of the first cut. The second cut will create a long, thin slice or strip of cake directly through the middle of the cake. This slice of cake will be 1 in (2.5 cm) wide but will be the entire diameter of the round cake.^{[18]
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- Again, you can cut a slice larger than 1 in (2.5 cm) wide, if you’d like.
4
Use your knife to remove the thin slice from the cake. Slide your knife under the cake, just underneath the thin slice that you created with the first two cuts. Carefully lift the knife so you can remove the thin slice from the middle of the cake.^{[19]
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- Serve and/or eat the thin slice of cake you cut out.
- You can cut this middle slice into small pieces if you’d like.
5
Slide the 2 ends of the cake together and secure them. Once you’ve removed the middle slice of cake, use your hands (or a spatula or knife) to slide the two ends of the cake together in the middle of the cake tray. Make sure the inside sections of the cake are touching each other. Secure the two ends together.^{[20]
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- The original method suggests securing the cake with a rubber band. However, this will only work if your cake has a harder exterior made of something like fondant (and isn’t very big).
- Alternatively, you could use a ribbon, a thin piece of parchment paper, or a piece of plastic wrap to hold the two ends together.
- You could also avoid securing the cake, as simply sliding the two ends together have probably protected the inside of the cake well enough.
6
Cut another slice from the middle, perpendicular to the first slice. When you’re ready for another slice of cake, take it out of the fridge and cut another slice from the middle of the cake. However, this time, cut the slice at a 90-degree angle to your original slice. Then repeat the same process of sliding the ends of the cake together for overnight storage.^{[21]
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- When storing the cake in the fridge, it’s up to you if you’d like to cover the cake with a lid or plastic wrap.
- The key to this method is that the inside part of the cake, or the sponge, will stay fresh because none of it is exposed to the air.
7
Repeat the process until the entire cake is eaten. Each time you want another piece of cake, repeat the same process. Each time you repeat the process, turn the cake another 90 degrees so you keep alternating the direction the slice is cut. (This will help ensure the two ends are always approximately the same size when they’re slid together.)^{[22]
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- Eventually, the pieces of cake left will be small enough to eat on their own and you won’t need to continue cutting pieces from the middle.