How to sharpen kitchen knives

The right kitchen tools and accessories can transform cooking from a necessary chore to a daily delight. Investing in a good collection of kitchen knives is a great start, making the culinary process quicker, easier, and more enjoyable. 

However, maintenance is also an important factor. Over time, knife blades can lose their sharpness, making them less effective. Knowing when and how to sharpen your kitchen knives can lead to smoother slicing, dicing and chopping. 

But what’s the best way to sharpen kitchen knives?

Why you should keep your knives sharp

Though it might seem counterintuitive, cooking with sharp knives is much safer than preparing food with blunt ones. When handling a blunt knife, you have less control over the blade, and it’s more likely to slip off the food you’re preparing.

Keeping your kitchen knives nice and sharp will not only make the cooking process safer, but it’ll also be quicker and more fun. And it’s not as complex as it might first appear. You don’t need to be a professional chef to sharpen knives, but keeping blunt blades away will certainly give you a cutting edge in the kitchen.

What’s more, a sharp knife can make your food taste better! It’ll give you finely diced and minced vegetables and wafer-thin slices rather than ragged chunks and torn ingredients.

How to tell if your knife is sharp enough

serrated knife cutting a tomato

The first thing to note when taking care of your kitchen knives is whether they are sharp enough for chopping or have become dull. The ‘paper test’ is an effective way to assess the sharpness of your knives.

To do this, you’ll need a folded (but not creased) piece of newspaper or a sheet of regular printer paper. Hold the paper by one end, lay the blade against the top edge at an angle and slice down and outward. A sharp knife should cut cleanly through the paper. If the slice isn’t clean, you can start by honing the blade with a knife sharpening steel. If, after honing, the knife still fails to slice the paper, you can sharpen it with a different method.

You can also try slicing a tomato to test the sharpness of your blades. If the knife cuts through the skin and flesh cleanly, your knife is sufficiently sharp.

How do knife sharpeners work?

There are several different tools to help sharpen kitchen knives. Essentially, each kind has a hard, rough surface. As you grind the knife against the surface, it sharpens the blade by shaving bits off to produce a new, sharp edge.

Not all knife sharpeners truly ‘sharpen’ a blade, however. Knife sharpening steels ‘hone’ the edge instead. 

Over time, kitchen knives can become dull because the blade becomes misaligned with use. Honing straightens the blade and pushes the knife’s edge back to the center without shaving the metal.

Whether you’re honing or sharpening your kitchen blades, always ensure safety comes first. And don’t worry, you needn’t sharpen your cooking blades every time you cook, although many professional chefs hone their knives daily. In fact, for sharpening, once every couple of months is enough to keep them in top form and stop too much metal from being shaved away.

Knife sharpening steel

man sharpening knife on a sharpening steel

As you can see, a knife sharpening steel hones rather than sharpens. Steels are long metal rods designed to keep already-sharp blades sharp. They have a hilt to hold and are perfect for regularly topping up sharpness rather than restoring a completely blunt knife.

When it comes to sharpening knives with a steel, you can try a couple of techniques. Use the method that feels safest and most comfortable to you.

A vertical hold is many people’s preferred technique. For this, hold the sharpening steel vertical, so it’s perpendicular to the kitchen surface. Place a sturdy chopping board, damp tea towel or cloth beneath the steel to keep it steady.

Holding the knife at a 20-degree angle, pull it downwards in a slight arc against each side of the steel, so both sides of the blade have contact with the rod. Afterwards, wipe the blade with a clean cloth to remove any excess particles.

More advanced chefs may prefer to hone their knives horizontally, in a floating hold. To hone your kitchen knives this way, hold the steel’s hilt close to your waist, so the length of the rod is sticking out away from you. Swipe the knife across the steel away from you, alternating the sides of the blade. Again, wipe clean with a cloth.

Electric Knife Sharpener

knife cutting fruit on a chopping board

Electric knife sharpeners are the most convenient option for restoring kitchen blades to their former glory. These gadgets consist of abrasive panels on motorized wheels that spin against the blade as you hold it in the machine’s slots. Electric sharpeners are handy for use on santoku knives.

Always follow the manufacturer’s instructions, as different machines vary. However, as a general guide, you can sharpen your knives with an electric sharpener in a few quick steps.

  • First, turn on the sharpener and hold your knife lightly but securely.
  • Pull the blade through the slot slowly and smoothly.
  • To sharpen both sides of the knife, alternate which side of the blade you pull through the slot.
  • Once you’ve sharpened both sides, carefully wipe the blade with a clean cloth to remove any loose particles.

Manual knife sharpeners

knife blade in a manual knife sharpener

Manual knife sharpeners work in a similar way to electric ones. However, rather than being on motorized wheels, the abrasive surfaces line a v-shaped chamber that you pull the knife through. 

When using a manual knife sharpener, use even pressure as you pull the blade through the chamber. A great upside of a manual sharpener is that they are suitable whether you’re left or right-handed. 


man sharpening knife on a whetstone

A whetstone, sometimes known as a sharpening stone, is essentially a rectangular block of stone that can sharpen knife edges. Whetstones have a coarse side to swipe the blade across. Some also have a finer side for honing.

To use one, first soak the whetstone in water until it stops producing bubbles. Remove it from the water and place the whetstone coarse-side up on a flat surface. It’s a good idea to set damp paper towels or a tea towel beneath the whetstone to prevent it from sliding about. 

Face the knife away from you with the blade’s side flat against the stone at a 20-degree angle. With one hand, hold the knife’s handle, and place fingertips of the other in the middle of the blade’s flat side to guide the movement down the stone in a broad, circular motion. Retain a constant angle until the tip of the knife runs off the other edge of the stone. 

Once done, you can repeat on both sides until the knife’s former glory has been restored.

This method does take some practice to master. However, if you’re willing to put in a bit of extra effort, the results are worth it. Plus, many people find the process quite therapeutic!

An extra benefit of a whetstone is that they’re suitable for sharpening pretty much any knife type, from utility knives to cleavers. Manual and electric pull-through sharpeners tend to be more limited in the blades they can handle. So a whetstone is ideal if you have a broad collection of specialist kitchen knives. 

Can you over-sharpen your knife?

You may wonder if using a knife sharpener can over-sharpen your knife or shave away too much metal. 

Sharpening knives too frequently with a coarse grinder can wear away the surface. However, with the right tools, your high-quality knives will be safe. Many electric sharpeners, for example, have multiple settings so you can decide how coarse or fine the abrasive surfaces are. If you’re a home cook rather than a professional chef, the finer slots are best for polishing up dull blades. Regular use won’t damage your tools.

Similarly, whetstones tend to have a coarse and a fine side. You can think of them as large, hard nail files (though perhaps don’t try and give yourself a manicure with one).

How to store your knife so it stays sharp  

zyliss comfort knives in a knife block

Once your kitchen knives are ship-shape, sharp and shiny, you might wonder how best to store them. 

If you like to keep your cooking knives in easy reach, why not store them in a robust knife block? The flexible fibers in the Zyliss Comfort Pro Knife Block protect blades and move easily to accommodate different knife shapes and sizes. Practical, organized, and stylish.

If you prefer storing your tools in a drawer, dedicated guards are a good option. We’re pleased to say that nearly all Zyliss Comfort kitchen knives come complete with blade guards. Not only do these prevent any accidental nicks as you reach into the utensil drawer, but they also prevent friction to keep your knives sharper for longer.