Early Prime Day Deals Best 5G Phones 2023 Cadillac Lyriq First Drive 4th of July Sales Prime Day Grill Deals The Right iPad for You PlayStation Prime Day Deals Best Standing Desks
We handpick the products and services we write about. If you buy through our links, we may get a commission. Reviews ethics statement

Stop Using a Knife to Slice Cake. This Method Is Faster and Cleaner

Grab this tool from your medicine cabinet for mess-free slices of cake.

Dental floss and container.
Grab some dental floss to slice your cake.
James Martin/CNET

This story is part of Try This, CNET's collection of simple tips to improve your life, fast.

When you've got a design-heavy cake, it's tough to keep the delicate piping in place when slicing it with a knife. Ultimately, you're left with smeared frosting and crumbs stacked on top of what used to be a perfectly iced cake. Fortunately, there's a surprisingly effective way you can cut the cake while preserving its beauty. Just put down the mess-causing knife and grab some dental floss instead.

A spool of dental floss tucks easily into a kitchen or desk drawer, or a work bag, and is always at the ready. I recently tested five types of dental floss to cut three types of cake. The result: some of the cleanest slices that would make any professional bakery proud. I'm not kidding. This method works fantastically well, and it's surprisingly easy to do. 

The only drawback: Using floss may not be the most elegant way to cut cake slices and you may get icing on your fingers. But the results are worth it. Here's how to cut your cake with floss, which type of floss works best and some pitfalls you should absolutely avoid. For more cool tricks, here's how to make distilled water for free and how to stop junk mail for good.

@cnetdotcom Your #cake may taste a bit #minty depending on the floss you choose. #lifehack#dentalfloss#trythis#didyouknow#cookinghacks#baking#howtotok♬ son original - SHIMMYA

Why use dental floss to cut a cake?

There may be a number of reasons you reach for the dental floss instead of a knife for cutting cake. Maybe you're in the office or at a birthday party in the park and the only available cutting utensil is a 6-inch compostable knife. Perhaps you're tired of buttercream buildup and want to try something new. One colleague saved the day at a celebration when a giant cube cake appeared at a bar that didn't have utensils for guests to use. Luckily, the container of floss she had on hand did the job.

CNET Try This

Here's why it works: A strand of floss is generally thinner than the average kitchen knife blade, and it's designed to slide easily through tight spaces (that is, between your teeth). If you've ever flossed too aggressively, sore gums are all the proof you need that the floss "edge" can be sharp. 

Add them together and you have a pretty ideal instrument that can get you neat, clean slices after cutting. While slicing through one cake, I could barely see where the floss sliced through the frosting because the cuts were so neat. 

In my experience, using dental floss to cut cake also did a better job of preserving the delicate decorations. For instance, the carrot cake I used for this test had a piped carrot design on top of the cake. Slicing through it with the floss kept that design intact. In my experience, using a butcher knife to cut through decorations often spoils the look, leaving a smeared design -- but it depends on the sharpness, width and length of the knife blade.

And that problem of accumulated frosting on the edge of the knife? Mostly gone -- with the exception of buildup on your fingers.

cake cut with floss

Pro tip: Slide the floss through the bottom of the cake for a cleaner cut.

Katie Teague/CNET

How to cut any cake using dental floss

First, make sure your cake is on a flat surface so you have room to pull the floss all the way to the cake's bottom. You could put it on a cake stand to give you more room as you slice down. Next, spool out a length of floss bigger than the widest part of the cake. I left several inches on each end to wrap the floss around my fingers comfortably. When you wrap the floss around your fingers, don't make it super tight: You're trying to cut cake, not your fingers. 

If you're trying to make each slice the same size, you may want to use the floss to lightly mark guide lines before cutting through the cake. 

Ready? Here's what to do.

Square or rectangular cake: If the cake is shaped like a square or rectangle, it may be easier to cut because those cakes are generally shorter than round cakes. Using your floss, make your cuts across the cake lengthwise, pressing firmly into the cake to cut all the way through. Now make your cuts widthwise, slicing to the bottom of the cake. 

Round cake: If your cake is shaped like a circle, it's possibly a layer cake so you may need to apply a bit more pressure to make it all the way to the bottom of the cake. Using your floss, firmly cut through the center of the cake to create two halves -- you may need to move the floss in a sawing motion to fully cut it. 

Then, make a perpendicular cut to the one you just made -- you should now have four triangles. Continue making cuts, moving around the cake, until you have the number of slices you need. Note that the thinner you want your slices, the harder it will be to cut because the slices begin falling apart.

cake cut with floss

Floss is better for cutting thinner slices of cake.

Katie Teague/CNET

Can you also use dental floss to serve cake slices?

To see if it was possible, I attempted to pick up a slice of cake with floss. It was tricky and kind of worked, but the floss slowly cut through the spongy texture as I tried to remove the slice. I suggest using a fork or serving knife to deliver slices to a plate, instead.

My pro tip for cutting cake with floss

When you're making cuts, once you've sliced to the bottom, don't pull the floss back up. First, doing that will make your floss messier, which means you'll need to get a new strand each time you make a cut. But more important, pulling the slice back up brings crumbs to the top of your cake and pulls up a bit of the frosting too, so you don't get the clean, tidy look you're after. 

Instead, once you've sliced all the way through to the bottom of the cake, let go of one end and pull the floss out. Most of the icing and crumbs on the floss will be swept off as you slip the floss out, and you'll be left with a clean strand that you can reuse to cut the next slice. 

Here's where the floss didn't do its job

When slicing the larger cakes, I noticed the floss sometimes didn't easily cut all the way to the bottom, maybe because of the increased resistance. If this happens to you, I suggest cutting the cake in half first and then working with each half so there's less cake -- and resistance -- to cut through. It might also help to put the cake on a stand to help you slice all the way through.

Another note: If you're baking a cake at home, this method won't work unless you remove the cake from the baking dish or cake pan first. 

Nice even slices of carrot cake

Nice even slices of cake.

Katie Teague/CNET

Which type of floss worked best

For my tests, I used waxed floss from Kroger, two types from Oral-B Glide (one mint flavored, the other unflavored), and two styles from CVS' store brand: a thicker, waxed dental tape and a regular, unwaxed floss. I tried the floss types on three cakes: A layer carrot cake containing bits of grated carrot, one taller and lighter texture sheet cake, and one shorter and denser sheet cake (almost like brownies).

All the floss worked great and made neat cuts, even with the bits of carrot from the more textured sample cake. The Glide original floss sliced through the cakes a bit easier than the Kroger waxed floss. I think it's because the Glide floss felt smoother to the touch and actually did glide through the cake. 

Despite my being worried that it would snag, the unwaxed floss worked surprisingly well and made neat slices.

The only one that smeared a bit when making a cut was the dental tape -- which looks more like a ribbon than a thread of nylon floss. It made a clean slice, though, and I'd use it in a pinch. 

Flavored vs. unflavored floss: Will it change the taste of your cake?

I was worried about whether using flavored floss would also transfer flavor to the cake slices, but we cut pieces of a chocolate sheet cake using mint-flavored floss and none of the four taste-testers could detect a minty flavor. To be safe, I'd stick with plain, unflavored floss if you can, and steer away from cinnamon or coconut or bubblegum flavors. 

So the next time you're cutting cake, reach for the dental floss or something similar -- like fishing line, sewing string or a thin wire.