If you have any experience with knives, you’d understand that with time they get blunt. Unlike other kinds of knives, sharpening a sushi knife requires precision and perfection. In this article, we’d be explaining how to sharpen a sushi knife in four easy steps. You do not need to be a professional blacksmith to sharpen your sushi knife at home or anywhere. With this guide, you have all you need to Sharpen any blunt knife to razor sharpness within minutes. All you need to Sharpen a sushi knife is a whetstone, pencil, water, and flattening stone. Without anything further, let’s get into the details.

How to Sharpen a Sushi Knife Easy Step

Step 1: Prepare the Whetstone

To properly sharpen a sushi knife, you would need a whetstone. Whetstone comes in different grit levels for grinding down metal and sharpening knives. For a professional-looking finishing and polishing, you should use a Whetstone with a high grit. First, start by submerging the Whetstone in water for about 10 to 15 minutes. When all the air bubbles have disappeared from the Whetstone, it means it has absorbed its maximum amount of water.

Note, ensure that the Whetstone you are using is completely flat. An irregularly shaped Whetstone can disfigure your expensive sushi knife. If your Whetstone is not completely flat, you can use a flattening stone, or a lapping plate to flatten it. Use a pencil to draw several marks on the Whetstone, preferably a grid to serve as a guideline of the Whetstone’s irregular or uneven parts. Rub the Whetstone against the flattening stone back and forth to chip off the uneven parts. When all the pencil marks are removed, it indicates that the Whetstone is flat and ready to use.

Step 2: Sharpening the Knife

After preparing the Whetstone, place it on a flat non-slippery surface or preferably on a whetstone holder. Use a Whetstone with a low grit for sharpening your Knife first. After setting up the Whetstone, move your blade back and forth across the stone’s length in a slow and light pressure. Make sure your blade is at an angle of 10 to 15 degrees or roughly your little finger’s height.

Start with the tip of the Knife first, and then slightly work yours through the middle and until you get down to the blade’s base. Repeat this several times or until you feel satisfied with the sharpness of the blade. Don’t forget to flip the Knife over to sharpen the other side. But some Japanese knives are only sharpened on one side, so ensure you check if your blade is sharpened before you flip it over. As you sharpen your Knife, you mustn’t press the Knife hard against the stone but glide gently over it.

Step 3: Polishing the Knife

Polishing your sushi knife after sharpening it on a whetstone is vital, especially if you want to get that razor sharpness. To Polish, your sushi knife, use the high grit side of the Whetstone. Like in the previous step, ensure the Whetstone is wet while you Polish the Knife. Also, maintain the same constant angle of 10 to 15 degrees as you Polish the Knife.

While you polish the Knife, you’d be tempted to wipe off the iron filling residue from the Knife, but don’t as it helps to further sharpen the Knife. When you are done polishing the Knife, rinse the Whetstone, and then wipe off the residue. Rinse your sharpened sushi knife in hot water, and you are done.

Step 4: Testing the Sharpness

Lastly, test the sushi knife’s sharpness to be sure it has the right sharpness for what you need. If you can effortlessly use the Knife to slice a piece of paper, it is sharp enough for sushi. Also, test the sharpness of the Knife by slicing a wet sponge. The Knife should be able to move the piece effortlessly, telling you it’s sharp enough for sushi.

Slicing tomato is another way you can test the sharpness of the Knife. If you can slice the tomato without touching it, congratulations, your Knife is officially razor sharp. Even if you do not have paper, sponge, or tomato close by, you can still test the Knife’s sharpness by shaving off some hair. Gently stroke the Knife on your hand to shave off some hair; if the Knife cuts the hair, your Knife is ready.


In conclusion, having an expensive sushi knife is one step. Knowing how to sharpen a sushi knife is another step to giving you that complete convenience when preparing your favorite dishes. Say goodbye to a blunt knife, as you can use these easy steps to quickly sharpen your Knife anywhere. If you have any question concerning the steps, kindly leave a comment in the comment section below, we’d be glad to offer you more assistance.

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