Japanese Knife Sharpening: Difference Between Sharpener and Whetstone

In recent years, many sharpeners have been developed to make sharpening easier and more accessible, and they are available through retailers such as Amazon. While sharpeners are a convenient tool to have, there are also several important drawbacks to consider.

Contrary to popular belief, the primary purpose of a sharpener is not to sharpen a blade's edge. Instead, sharpeners temporarily improve a blade's ability to grip food by roughening the blade's edge. As a result, a sharpener cannot replace whetstones for sharpening kitchen knives because the latter sharpen a blade's edge instead of damaging it. Overreliance on sharpeners for sharpening can cause the blade's strength to decrease significantly, leading to cracks and chips.

whetstone knife sharpener whetstones

To maintain the sharpness of a kitchen knife, we recommend using a whetstone to sharpen the blade once or twice a month, in addition to using a sharpener. If you feel that the knife's sharpness has decreased while cooking and don't have time to use a whetstone, a sharpener can temporarily improve the knife's cutting ability. However, it is not recommended to rely solely on sharpeners as a maintenance tool.

There are several types of sharpeners available, including rotary whetstones, electric sharpeners, and water whetstones, but they all work similarly. Depending on the type of sharpener, you may need to push or pull the blade or move it in a particular direction, so it's essential to read the instructions carefully.

Amazon offers a wide range of whetstones and sharpeners. Regardless of the tool you use, we recommend sharpening your knife regularly to maintain its edge.

Comparison of Sharpeners and Whetstones

Now let's take a closer look at the difference between a blade that has been sharpened with a sharpener and one that has been sharpened with a whetstone.

A new kitchen knife's edge is incredibly sharp, as it has been meticulously crafted through a series of processes, including sharpening. This process involves gradually changing the buffing tool, made of materials such as cloth, leather, and vinyl, until the blade's edge is completely smooth and free of scratches.

When we sharpen a knife, we strive to achieve a similar level of sharpness. However, over time, a blade will inevitably begin to wear down, and the edge will become dull. Using a sharpener will temporarily improve the blade's cutting ability by roughening the edge. On the other hand, using a whetstone will sharpen the blade's edge, resulting in a much sharper knife.

In summary, while sharpeners are a convenient tool to have, they cannot replace whetstones for maintaining a knife's sharpness. Using a whetstone once or twice a month, in addition to using a sharpener when needed, is the best way to ensure that your kitchen knife remains sharp and effective for years to come.

Related products

1 review

Gyuto Knife with Japanese Handle - All-purpose Premium Japanese Artisanal Knife

$360.00

Quick view

The Japanese Gyuto knife is the ultimate multi-purpose blade, perfect for everyone from beginner home cooks to seasoned chefs. As the Japanese counterpart to the Western chef’s knife—only thinner, lighter, and sharper—it excels at chopping, slicing, and dicing almost anything in the kitchen with effortless precision. This variation features a beautiful maple-wood handle that not only adds a natural, elegant aesthetic but also provides a smooth, earthy texture for enhanced control and comfort. Crafted with CM stainless steel, it offers exceptional sharpness, durability, and rust resistance, ensuring years of effortless slicing. With a blade length of 180mm (7.1 inches) and a double bevel edge, this handmade, hand-braided, and hand-sharpened Gyuto is a versatile and essential tool that elevates both the appearance and taste of your culinary creations. This product is available for shipping within the USA only.

View Product

Santoku Knife - Premium Japanese Artisanal Knife

$250.00

Quick view

The Santoku knife is revered for its control, precision, and sharpness, making it the master of slicing, mincing, and dicing in both professional and home kitchens. Traditionally favored for high-precision tasks like sushi and sashimi preparation, its versatility extends to cutting meat, fish, and vegetables with ease, supported by a comfortable, easy-to-control handle. Handmade by master bladesmiths using techniques passed down through generations, each Santoku offers extraordinary quality that elevates every slice. Named after the "Three Virtues"—meat, vegetables, and fish—the Santoku’s shorter, thicker, straight-edged blade with a sheep foot-shaped tip enhances the appearance, taste, and texture of your food while delivering exceptional performance with minimal maintenance, thanks to its CM stainless steel and Western-style handle. With a blade length of 170mm (6.7 inches), it is the ultimate daily knife for any cooking enthusiast.

View Product

1 review

Petty Knife with Japanese Handle - Premium Artisanal Knife

$179.00

Quick view

The Japanese-style Petty Knife is a premium artisanal blade designed for maximum control and precision, perfect for peeling, slicing, shaping, and trimming in tight spaces. Its fine-tipped 150mm (5.9 inches) blade unlocks new levels of creativity in shaping and presentation, helping elevate the beauty of every dish you create. Featuring a traditional maple-wood handle, it offers a smooth, natural texture that feels as good as it looks, making it a joy to use. Handmade and sharpened by master bladesmiths, this knife guarantees prolonged sharpness, durability, and effortless slicing for years, making it an essential tool for passionate home cooks and professional chefs who take pride in every cut. Crafted from CM stainless steel for rust resistance and low maintenance, the Japanese Petty Knife blends beauty, functionality, and lasting performance into one exceptional kitchen companion.

View Product

1 review

Nakiri Knife - Vegetable Cutting/Slicing/Mincing Premium Japanese Artisanal Knife

$290.00

Quick view

The Nakiri knife (菜切包丁) is a highly versatile and efficient tool, traditionally used in Japan for cutting vegetables with supreme speed and precision. Its thin, lightweight rectangular blade allows for quick, clean, and effortless slicing without the need for a rocking motion, keeping your knuckles safely away from the cutting board while delivering beautifully thin, even slices every time. Perfect for delicate vegetables and even light filleting tasks, the Nakiri offers incredible control and minimizes damage to ingredients, preserving their flavor and texture. Handmade and sharpened by master bladesmiths, this 165mm (6.5 inches) knife features a traditional Japanese magnolia wood handle with a plastic collar and is available with either CM Stainless for easy maintenance or Kasumi Superlative Carbon Steel for a more traditional sharpening experience. With its unparalleled usability from tip to tail, the Nakiri is an invaluable asset for anyone seeking speed, consistency, and elegance in their kitchen work.

View Product

Difference Between Sharpener and Whetstone — Frequently Asked Questions

Are pull-through sharpeners safe for any kitchen knife?

For soft Western steel (54–58 HRC) on cheap kitchen knives, yes — they'll pull a working edge that lasts a few weeks. For Japanese knives at 60–63 HRC, no — the carbide blades inside a pull-through sharpener strip a huge amount of steel at a fixed angle that probably doesn't match your knife's original geometry. Within a few uses your blade is shorter, the edge is wrong, and the knife is permanently changed. Even "ceramic" or "diamond" pull-through sharpeners are worse than a 1000-grit whetstone for a Japanese knife. Read our whetstone tutorial for the right method.

How to Sharpen a Knife Using a Whetstone

What about electric sharpeners — are those any better?

Slightly better than pull-through manuals, still wrong for Japanese knives. Electric sharpeners use spinning abrasive wheels at preset angles (usually 18–22 degrees per side, the Western default). Japanese kitchen knives are sharpened at 12–15 degrees per side, so the electric sharpener over-grinds the edge and changes the geometry every time you use it. They're also aggressive — they remove far more steel per session than necessary. For Japanese blades, stick to whetstones or send the knife to a professional sharpener who knows Japanese geometry.

When IS a sharpener actually appropriate?

For a $20–40 stainless paring knife or bread knife you don't care about, a pull-through sharpener is a fine quick fix. For your good Japanese gyuto, never. The general rule: the cheaper and softer the knife, the more forgiving it is of pull-through sharpeners; the more you spent on a Japanese knife, the more important it is to use whetstones. If you're bouncing between cheap and quality knives, get the whetstone — it works on everything, while a pull-through only works on the cheap ones.

Can a honing rod replace whetstone sharpening for Japanese knives?

No — honing rods do almost nothing for Japanese steel. A honing rod realigns a microscopic edge that has folded over from use, which works on softer Western steel where the edge bends. Japanese knives are hardened so much that the edge doesn't bend; it dulls by tiny chips instead. So a honing rod doesn't restore the edge meaningfully; only a whetstone removes the dulled steel and exposes a fresh edge. If you currently use a steel rod on Japanese knives, you can stop — it's not actively damaging, but it's also not helping.

How much should I budget for a starter whetstone setup?

$50–80 covers everything a beginner needs: a 1000/6000 combination stone (about $30–40), a stone holder or non-slip mat ($10–15), and a small spray bottle for water. That's it — no fancy guides, no five-grit kits. The 1000-grit side handles maintenance sharpening and the 6000-grit polishes the edge. Once you've sharpened a few times, you can add a 220-grit stone for chip repair ($25) and eventually a flattening plate for the stones ($30–60). Read our sharpening stones guide for the brand picks.

Choosing Sharpening Stones for Japanese Knives

• Disclosure: I only recommend products I would use myself, and all opinions expressed here are my own. This post may contain affiliate links that I may earn a small commission at no additional cost to you.
The commission also supports us in producing better content when you buy through our site links.
Thanks for your support.
- Kei and Team at Dream of Japan

Get Free Bonus Books

Sign up for free to the Japanese Knife Club to get advice and exclusive articles about how to choose Japanese Knives, and tips and tricks for using Japanese knives.

Unsubscribe anytime. It’s free!

About the author

Kei Nishida

Author, CEO Dream of Japan

info@dreamofJapan.com

Certification: PMP, BS in Computer Science

Education: Western Washington University

Kei Nishida is a passionate advocate of Japanese craftsmanship, a writer, and the founder and CEO of Japanese Knife Co., Japanese Green Tea Co., and Japanese Coffee Co., all part of Dream of Japan.

His journey began with a mission to introduce the world to the exquisite flavors of Japanese green tea. Through Japanese Green Tea Co., he pioneered the import of premium tea grown in nutrient-rich sugarcane soil, earning multiple Global Tea Champion awards. He then expanded into the world of coffee, launching Japanese Coffee Co., the first company to bring Sumiyaki charcoal-roasted coffee to a global audience.

With a deep appreciation for Japanese artistry and tradition, Kei turned his attention to one of Japan’s most revered crafts: bladesmithing. Through Japanese Knife Co., he made handcrafted katana-style knives, created by a renowned katana maker, available outside Japan for the first time. These exceptional knives embody centuries of samurai sword-making expertise, blending tradition with modern functionality for chefs and collectors alike.

Kei’s journey continues as he uncovers and shares Japan’s hidden treasures—one sip, one blade, and one legacy at a time.