Top 17 Best Japanese Knife Sharpeners to Buy Online 2020 - Tried and True!

Here are the top knife sharpeners we bought and tested out. See how they rank below and make your choice!

And why they didn't quite make it.

This knife sharpener from Seria 100-yen shops is not all that bad. It's certainly cheap, and it does a reasonable job of sharpening. It's small and you can throw it in a drawer. But because it's so small, we didn't like how close our hand was to the blade while we were sharpening. Be careful when you use it.

Kakusei's Flexible Diamond Sharpener is average as far as ease of use and the results we got on our knives. It takes a little practice to get the technique down for this type of sharpener, but it's cheap, so may be good to practice with. Mostly we'd recommend it for using to sharpen your slicer blades instead of knives. The thin profile makes it perfect for that.

This double-sided whetstone from Daiso 100-yen shops is a good choice if you want to go old school. It's not easy to use, but once you know how, you can get a nice, sharp edge. 

Whetstones are not quite fine enough to use as honing tools, however, and the process of soaking the stone in water before use is a bit annoying. If you consider caring for your kitchen knives as meditation, it could be right for you.

Our top choice was a Kyocera, but this battery-operated one is nowhere near as good. Granted, it's simple to use, but it just doesn't sharpen well enough. It does have a display that shows you the battery status and correct operation, so it's suitable for beginners who want an electric sharpener.

The Bounding X Sharpener from Kyowa is stable and can be gripped firmly, but it's hard to use anyway. You have to pull the blade through one of the two whetstones at an upward diagonal angle.

This diamond and ceramic sharpener from Kaijirushi is compact and slides into its case for protection during storage. Performance was average, but it was hard to use.

This sharpener from Daiso is supposed to stick with a suction cup but it may not depending on where you install it. It sharpens well, and it's very small, but be really careful that's it's stuck securely before you use it.

Togi Power from Shimomura Industries is a compact battery-operated sharpener. You can't wash it with water, it wasn't that easy to use, and it didn't sharpen as well as manual ones.

This whetstone from Hiveseen is only suitable for honing already-sharpened blades. Like all square stones, it takes practice to use it correctly. This one also takes time - about 20 strokes per side on each side of the knife. It could be good as a honing stone after using the whetstone from Daiso to repair major chips first.

We ran each product through tests to check for the following:

1. Sharpening ability
2. Ease of use

We used knives from the 100-yen shop for this test. We either followed the manufacturer's instructions; or, if the sharpener had no instructions, we ran the blade through it five times.

We stacked 24 sheets of paper and folded the stack in half. Then we cut the paper 10 times with our newly-sharpened blade. A 10.6-ounce weight was attached to the blades to keep the force consistent. Then we checked to see how many sheets of paper were cut.

We learned that when it comes to sharpening, square, coarse-grained whetstones are the best! Daiso's stone has a grit of #80-#220, and the knife sharpened with it left deep, clean cuts in our paper.

On the other hand, the whetstone from Hiveseen was too fine, with a grit of #1000 and #4000. It would only be good for honing an already sharp blade. To revitalize a really dull knife, it's worth learning how to use a coarse whetstone.

While sharpening our knives, we considered how easy or difficult our task was. Was the sharpener stable and easy to grip? Was sharpening easy? Could it be washed quickly? Were there any features that made it better or worse than others?

We found that if you prioritize ease of use, your best choice is something simple that can be gripped firmly and has a guide cover. Most of the models we tested fall into this category, but their features varied.

Look for one that has a guide which takes the guessing out of what angle to insert the blade. An arched handle makes it safer to hold onto. Basic manual sharpeners are easy for beginners. And if you get one where you can change the sharpening stones, you'll save money and be able to keep it clean.

Before you buy a sharpener, we recommend considering these two points.

There are four main types of sharpeners.

• Manual sharpeners with guides
• Sharpening rods/sharpening steels
• Square whetstones
• Electric sharpeners
  

Let's look at the pros and cons of each type.

Sharpeners with guides are probably the most commonly sold nowadays. They consist of a V-shaped groove with crossing whetstones or blades and you slide the knife through to sharpen. They're compact and can be used spur of the moment. Some require you to move the knife back and forth, while others should only use a pulling motion, so check the product before you use it.

Their main drawback is that the cutting stone only hits the very edge of the knife blade, creating a shallow V which dulls quickly. They also vary in their ease of use (so check our rankings!)

These are easier to use than square whetstones, but give a better edge than V-shaped sharpeners. They are not as user-friendly as ones with guides, but once you get the hang of it, they'll give you better results and can be used on a larger variety of blade shapes. 

They're fairly compact and thin, so they can fit in a drawer. Don't get one that's too short, though, or it will be even more difficult to use.

These require the most practice and patience to use, but everything worthwhile takes time! Traditional whetstones will still provide superior results. When used correctly, they will produce razor-sharp blades that keep their edge far longer. That's why these are still the first choice of professional chefs.

Look for one that has two different levels of fineness on each side, and consider pairing it with stoppers to help you keep the proper blade angle.

Although they're more expensive and louder, electric sharpeners can give you a good edge with little effort. They basically work the same as manual V-shaped types, but the motor means you can sharpen quickly, without having to move the knife so many times. They take up a little more space, and of course you need to be careful about not getting them wet.

Most of these sharpeners are for stainless steel double-edged knives. If you have a specialty knife, be careful to get a sharpener that works on it.

Traditional Japanese santoku knives are often single-edged, and these will require a special sharpener. However, many santoku sold recently for home use are double-edged. There are a limited number of sharpeners that can handle single edges, sashimi knives, or serrated edges, but if the sharpener doesn't specify, don't try it.

You also need to check your blade's material. For ceramic or titanium knives, make sure the sharpener has the right grindstones to use with that knife. Some sharpeners come with a few choices for grindstones, and these are ideal if you have a variety of different knives in your kitchen.

Different types of sharpeners require different techniques, but here are some general tips to help you get the best results.

• Don't use excessive force. Not only will the blade be likely to skip, leaving a jagged edge, but it could even cause it to chip.

• Don't go too fast. You may knock over the sharpener when the blade is released and injure yourself. Use slow, steady strokes.

• Square whetstones take some practice to keep the angle right. You can use disposable chopsticks as a guide to help you until you get the hang of it!
  

Lucky for you, our team of editors and experts has tested out a lot of other kitchen tools you can use to slice and dice anything you want.

After testing all these different types of knife sharpeners, we feel that the combination of a simple manual sharpener and a traditional whetstone produces the best results. Whatever you choose, make sure to follow our advice to find the best one for you!

Writing: Kano Ichiyama/Translation: Susan Lucier-Ogawa/Photos: Koichi Miura, Yuki Inagaki

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