How to Sharpen a Serrated Knife: A Complete Guide with Tips, Tricks and Step by Step Instructions
I love my serrated knives – they are my secret weapons in the kitchen. Perfect for slicing through delicate foods with tough exteriors, items like bread, tomatoes and even some types of citrus, serrated knives are a must have in any well stocked kitchen.
But alas, serrated knives dull over time, as all knives do, and need to be sharpened. And here’s the thing – sharpening a serrated knife, while not necessarily difficult, is actually quite different from sharpening a regular, straight-edge chef’s knife.
I’ll walk you through everything you need to know about how to sharpen a serrated knife, with a few tips, a couple tricks, and step by step instructions for getting your serrated blades ultra sharp.
Can serrated knives be sharpened?
Yes, you can absolutely sharpen serrated knives. In fact, sharpening serrated knives is in many ways easier than sharpening a flat edged blade, and takes even less skill to master.
Serrated knife blades are distinct for the alternating scalloped indentations and many teeth that line the blade edge. These teeth are ideal for cutting through foods with relatively hard exteriors, and reasonably soft insides, like bread, and even tomatoes.
But because of the shape of a serrated knife blade – what is essentially a series of alternating V and upside down U shapes – you will need to use a specific technique to keep them sharp. In order to return your serrated knife to its glory days, you will use either a ceramic sharpening rod, a specifically designed serrated knife sharpening tool, or, as I demonstrate below, the bottom of a ceramic plate!
Can you sharpen serrated knives with a whetstone?
Serrated knives cannot be sharpened with a conventional whetstone. Instead, you will need a ceramic honing rod, or a variant of this tool made specifically for serrated blades.
Whetstones are amazing tools for sharpening flat edged knives at home, but given their shape, they only work with smooth blades. This really is a square peg in a round hole sort of problem.
If you try to sharpen your serrated blade on a whetstone, you’ll just end up wearing down the pointed tip of each tooth (what I mean here is, the V’s) without doing anything to sharpen the inner concavities between points (think, the upside down U’s).
Trying to sharpen a serrated knife with a whetstone will damage your blade far more than help it, essentially removing the very properties that serrated knives use to function. In fact, using a whetstone on a serrated knife will actually accelerate the natural process through which serrated blades get dull – wearing down the teeth.
Are you supposed to sharpen serrated knives?
It is perfectly fine to sharpen serrated knives, but serrated blades require sharpening far less frequently than conventional kitchen knives. This is because the sharp edge on a serrated knife is recessed, and rarely makes contact with the cutting board.
The truth is, the blade edge on your kitchen knives get dull not from the food that you cut, but rather, from the cutting board on which you prepare your food. Food isn’t responsible for dulling your knife, your cutting board is.
If you think about it, your chef’s knife makes nearly constant contact with the board as the flat edge of your knife repeatedly kisses the flat surface of the board, while only the teeth of a serrated knife ever touch the cutting surface.
This results means that over time, those teeth, which were once V-shaped, wear down, until they start to look more U-shaped. See how, in the photograph above, the teeth are completely worn down?
This serrated knife is definitely a candidate for resharpening. The teeth are worn down to just nubs. And yet, the recessed part of the knife, those gaps between teeth, is actually still quite sharp.
This can be both good and bad. On the plus side, about 95% of the edge of your serrated knife – the concavities between teeth – remain sharp almost all of the time. That means your serrated knife will continue to work, and work well, even after the teeth have gone dull.
And therein is the bad side. You might not notice it, but the serrated knife that you’re using every day can probably be sharper – much sharper.
How to sharpen serrated knife blades
The proper way to sharpen a serrated blade is with a ceramic honing rod. Nestle the tool between two teeth, perpendicular to the blade, and using the concavity as a guide, push the honing rod several times away from you.
Sharpening a serrated blade is actually quite easy, and in fact, it’s pretty hard to mess up. But here’s the rub – you’re going to need either a ceramic sharpening rod or a sharpening tool specifically made for serrated blades.
In general, steel honing rods are far too big to be used for serrated blades, even those with large scallops. They simply don’t fit between the teeth. But even more importantly, steel honing rods aren’t actually abrasive enough to do anything to serrated teeth, even if they did fit.
Take a look above, and you’ll see that my sharpening steel (actually a honing steel) is both too thick to fit into the grooves of my serrated knife, and insufficiently textured. I’ve included this photograph as an example of what DOESN’T work when it comes to sharpening serrated blades.
Steels like the one I’m using are generally textured so that they create friction with blades on a perpendicular angle. And while you are also meant to hold a serrated knife perpendicularly to the honing rod, serrated knives pass along the rod, rather than across it.
So, even if my steel did fit between the grooves on my serrated knife, the steel doesn’t actually have enough grit to do much. This is a waste of time and energy.
Steel honing rods are meant to hone, not sharpen. I know this can be confusing, but in essence, honing is a practice of re-aligning the existing edge on your knife, while sharpening is a practice of removing material on your dull blade to create a fresh, newly sharpened edge.
When you sharpen your serrated knife, you need to actually sharpen – this means you need to remove material from the concavities between teeth in order to create new points. A standard steel honing rod will not be able to do this.
Can you sharpen a serrated knife with an electric sharpener?
Oftentimes, an electric sharpener can be used to sharpen serrated knives, but it must be built with that explicit capability. Unless otherwise stated, everyday electric sharpeners will not work on serrated knives.
That said, there are a few electric sharpeners out there that I like quite a bit, and which were designed to work well with serrated knives. This is particularly convenient, because as we know, electric sharpeners are fast, consistent and efficient.
If I were to recommend an electric sharpener that is compatible with serrated knives, then I would probably have to go with the Chef’s Choice 15 Trizor XV.
Chef’s Choice 15 Trizor XV EdgeSelect
There’s a lot to appreciate with this machine. It utilizes a three stage system, which means that the sharpening station is incredibly versatile.
Stages one and two are plated with 100% diamond abrasives, and can be used to sharpen and hone straight-edged knives, like your chef’s knife or a Santoku, while stage three uses a patented, flexible abrasive system to polish and prolong the life of serrated blades.
In addition, the 15 Trizor XV has a few extra perks:
- First, this system is incredibly easy to use, and has flexible spring guides that automatically adjust for accurate sharpening angles. This eliminates guesswork.
- Second, the 15 Trizor XV combines “the strength and durability of the Trizor edge with the flawless, ultra-sharp 15-degree XV technology.”
- Third, the 15 Trizor XV is super fast – sharpen your knife in under one minute, or hone in a matter of seconds.
- Lastly, Chef’s Choice backs this product with a three year, limited warranty.
How to sharpen a serrated knife without a tool
The best way to sharpen a serrated knife without a tool is with the bottom of a ceramic plate, known as the foot-rim. Foot-rims are perfect for sharpening the divots between teeth, and are used identically to ceramic rods.
I actually learned this trick from everyone’s favorite French chef, Jacques Pépin. Jacques is full of fantastic kitchen tips, and I fully recommend following him on all of your social media channels. He’s such a delightful presenter, so knowledgeable, and endlessly humble.
The way Chef Pépin explains it, ceramic is coarse enough to sharpen knives – and this makes perfect sense, since it’s often used to make sharpening rods as well. The bottom of a ceramic plate is what you want, because the foot-rim, the part you will use to sharpen your knife, will be free from glaze and coarse enough to actually work.
As you can see below, I’m using one of my plates to sharpen some of the duller knives in my set. The results were even better than I expected!
To sharpen your serrated knife using the bottom of a plate, you will:
FIRST: Locate a ceramic plate that actually has an exposed, rough edged foot-rim. Not all plates are created equal, and some have foot-rims while others do not.
The type of foot-rim is also critical here – it must be unfinished (i.e., unglazed) and it must be relatively thin, such that it fits snuggly into the grooves of your serrated knife.
SECOND: Turn your plate over, and rest it on a stable surface where it won’t slide around. I like to use a cutting board, but you could also use a damp dish towel. The point is to prevent your plate from moving, even as you put pressure on it from above.
THIRD: Beginning with the tip, place your knife perpendicular to the foot-rim such that the rim fits inside the scalloped knife edge. You will also hold your blade at a slight angle, most likely about 15 to 20 degrees.
Luckily, you don’t have to think too much about blade angles here – the way you might with a whetstone – because the grooves are already cut. You are simply using the existing grooves as a guide. Position your knife so that the concave divot between knife teeth fits onto the foot-rim, and gently apply pressure while sliding the blade away from you.
Depending on how dull your blade may be, you may want to do anywhere from two to five or even six passes (again, pressing the knife blade to the foot-rim, and sharpening away from you) for each divot.
As you can see, I’ve switched to one of my duller knives and am currently about halfway through the sharpening process. This one really needed some love.
You may notice that the bottom of your plate darkens as the knife blade passes over it. Don’t worry, this actually means that the process is working – the dark material isn’t coming off the plate, but rather, from your knife. Little by little, you are removing layer after layer of metal from between the teeth of your knife, and in so doing, creating new teeth.
And because this dark color is coming from the knife, rather than the plate, it wipes right off! I promise you that this will not ruin your plate. Ceramic is hard, and that’s why we’re using it!
FOUR: Once you’ve sharpened each individual divot of your serrated knife, take a step back and examine your work. It will be hard to gauge the sharpness of the concave scallops, but what you are looking for here are newly sharpened, more pronounced teeth.
If your serrated knife was very dull, the teeth would have been very worn down. In sharpening the knife using the method above, you were essentially stripping material from between the teeth to create new points.
If you are satisfied with the newly pointed teeth on your knife, it’s time to move on to the next and final step. However, if you see some progress but think your serrated teeth could still be pointier, I would advise returning to step three and doing a second pass over the entire knife.
FIVE: Ok, you’ve sharpened each divot, and created some super sharp, very pointy teeth. Now turn your blade over and examine the other side.
Chances are, you will see some small irregularities, or burrs, on the side opposite the scallops, where metal was pushed up, and away, but wasn’t completely removed from your knife. In this final step, you will be removing those imperfections.
As I am doing above, turn your knife over and place it across the plate, such that the blade is perpendicular to the foot-rim in two places. If your knife is too small or your plate too large to make contact when the knife is positioned at the plate’s diameter – as I have it above – position the knife lower down on the plate.
Moving the knife lower on the plate (creating a shorter secant, for all you geometry nerds out there), will ensure that the knife still makes contact in two points. Doing this, and laying the blade flat, will stabilize the knife, and set the edge flush with the ceramic.
Now, gently and slowly pull the knife away from the plate, while maintaining consistent pressure against the foot-rim. Be very careful not to twist the knife on its long axis here, since that will place the tips of your newly sharpened teeth in direct contact with the ceramic, essentially undoing your sharpening work.
Repeat this process two to three times only, just enough to remove the metal burrs that may have been worked up during step four.
That’s it! Give your knife a good washing with soap and water, just to remove any lingering debris, and then dry your knife with a clean towel. Congratulations – you’re good to go!
When would you use a serrated knife?
Serrated knives are used on foods that have a tough exterior but are still quite delicate. For example, a serrated blade is ideal for slicing into ripe tomatoes, or through the crust of fresh bread.
When you try to slice into foods like crusty breads and tomatoes with standard, flat-edged blades, you risk crushing the food before even penetrating the crust. We’ve all been there, you’re trying to slice a tomato and can’t even get through the skin, so you press a little harder and boom, tomato pulp everywhere!
The same is true of bread. Imagine trying to slice through a fresh, crusty loaf of bread with a chef’s knife! Bad idea.
I took this post on serrated knives as an excuse to do a little baking, and made a quick, crusty loaf in my dutch oven. As you can see, I’m slicing through it effortlessly, using of course, my serrated bread knife!