What is a Japanese kitchen knife? Shapes, edges and steels explained

A knife for one sheet of daikon

There is a Japanese knife built to turn a daikon into one long, thin sheet. The cut is called katsuramuki, and the knife is the usuba, 薄刃, a straight-edged vegetable blade sharpened on one face only¹. The name means "thin blade". Korin, the New York importer, says the square-tipped usuba comes from Kantō, around Tokyo, and the pointed kamagata usuba from Kansai, around Osaka⁴.

Hold an usuba next to a gyuto and the word "Japanese" starts to look too broad. One is a specialist tool with a flat back. The other is a Western chef's knife reworked in Japan. Both are Japanese kitchen knives. Most of the splits in this guide show up in the usuba, so it is a good place to start.

Two families, told apart by the blade

Japanese cooks sort kitchen knives into two families. Wa-bōchō, 和包丁, are traditional Japanese shapes. Most are single-bevel, usually with a plain wooden handle, and built for jobs such as sashimi, vegetables and fish. Yō-bōchō, 洋包丁, take their shapes from the West, the gyuto and the petty among them. Most are sharpened on both sides and do general work¹.

The handles split the same way. A wa handle is straight and simple, usually wood, pushed onto a narrow tang. A yō handle is the Western kind, riveted on either side of the tang and shaped to fill the palm¹. Handles no longer settle the question, though. Hocho Knife's Sakai Takayuki range lists gyuto with both kinds¹¹. Look at the blade's shape to tell the families apart.

One sharpened face, or two

The usuba's flat back is the difference you will feel first.

A single-bevel knife, kataba, 片刃, is sharpened on one face. The other face is flat or slightly hollow¹. Korin says the hollow back, the urasuki, gives a keener edge, easier resharpening and finer work, and ties the design to Japanese cooking's focus on clean cuts of fresh ingredients². The edge also steers to one side. Single-bevel knives come in right- and left-handed versions, and Korin notes that one cannot be converted into the other²¹.

A double-bevel knife, ryōba, 両刃, is sharpened on both faces, like a European chef's knife. Korin calls it a stronger edge that suits any kitchen². Many Japanese double-bevel knives are still lopsided on purpose. Makers often grind more of the bevel onto the front face, at ratios such as 70:30, to get closer to single-bevel sharpness².

Seven shapes, and what each one is for

Korin notes that sushi chefs treat the yanagiba, deba and usuba as the core of a traditional set². In Japanese homes, the popular all-rounder is the santoku¹.

Gyuto, 牛刀

Japan's version of the Western chef's knife, used for meat, fish and vegetables¹. Korin calls it extremely versatile and suited to Western cooking, with a name for a light, thin blade².

Santoku, 三徳

A double-bevel all-rounder for meat, fish and vegetables, popular in Japanese homes¹.

Nakiri, 菜切

A rectangular double-bevel vegetable knife, easy for home use¹. Knifewear, a Canadian retailer, points out that its flat edge meets the board along its whole length, so a push-and-pull chop cuts all the way through³.

Petty

A small all-purpose knife for fine prep and fruit¹.

Usuba, 薄刃

The katsuramuki knife from the opening, single-bevel and straight-edged, also used for fine julienne¹.

Yanagiba, 柳刃

The long, slim single-bevel slicer for sashimi. It cuts in one long pulling stroke¹⁴.

Deba, 出刃

A thick, heavy single-bevel knife for breaking down fish¹. Korin warns that it is not meant for chopping through large bones or for cleaver-style blows⁴.

Four more you will meet in shops

• Sujihiki, 筋引, is a long, narrow slicer for trimming sinew from large cuts of meat and slicing them¹.
• Takohiki, 蛸引, is the square-tipped Kantō sashimi knife¹⁴.
• Kiritsuke, 切付, is a single-bevel knife with an angled, clipped tip that does the work of both yanagiba and usuba. People call it the head chef's knife, but a Tokyo retailer stresses that this is custom, not a rule. Double-bevel "kiritsuke gyuto" exist too¹.
• Honesuki, 骨スキ, is a small, stiff, triangular knife for breaking down meat and poultry¹.

Length, in sun and millimetres

Japanese shops often give blade length in sun, 寸, a traditional unit of about 3.03 cm. A 7-sun knife is about 21 cm¹. Listings usually add the edge length, the hawatari, in millimetres, measured from the heel, the machi, to the tip¹.

Words that describe the surface

Many product names describe the finish rather than the steel underneath.

• Kurouchi, 黒打, is the black forging scale, left on the blade as a rustic finish¹.
• Tsuchime, 槌目, is a hammered, dimpled finish¹.
• Nashiji, 梨地, is a fine matte texture named after pear skin¹.
• Damascus or suminagashi means layers of different metals forged together to show a wood-grain pattern¹. Korin notes that layered blades have caught on for their looks and their properties⁴.
• Kyōmen, 鏡面, is a mirror polish¹.

Carbon, stainless, or both

Carbon steel

Traditional Japanese knives use carbon steel, usually called hagane, 鋼. It takes a very sharp edge and sharpens easily, and it rusts if left wet¹. Korin tells owners to wipe carbon knives dry even mid-task, and says acidic food will discolour them without hurting performance⁵. The best-known names are the "paper" steels from Proterial, formerly Hitachi Metals. Shirogami, white, is the base. Aogami, blue, adds chromium and tungsten for wear resistance¹⁶.

Stainless steel

Stainless steel carries enough chromium to resist rust. It is easier to look after, and its cutting performance varies a lot from grade to grade¹. You will see VG10, SG2/R2 and Ginsan on Japanese blades. Ginsan comes from the same steelmaker as Shirogami and Aogami, and turns up in traditional shapes because it sharpens fairly easily¹⁶. Korin still says to wash stainless knives after each use, because salt and acids wear away their protection⁵.

Clad blades

Many knives combine the two, with a hard carbon-steel core between softer stainless layers. Knifewear says this gets you most of carbon steel's sharpness with less fuss. The exposed edge can still rust and needs wiping dry³.

Kasumi, honyaki and the san-mai sandwich

• Kasumi, 霞, "mist", is hard steel forge-welded to soft iron. Polished, the iron looks hazy, hence the name¹⁴. Sakai's traditional knives are built this way, a soft iron body with a hard high-carbon edge, so the blade neither snaps nor bends and still cuts well⁷.
• Honyaki, 本焼, is one steel throughout. Clay goes on before quenching so only the edge gets fully hard¹. Korin says honyaki holds an edge longest but is harder to sharpen and more likely to chip or crack if misused⁴. The Sakai maker Jikko says honyaki is unsuited to cutting hard foods⁸.
• Warikomi or san-mai is a steel core between two outer layers¹.

Hardness on the Rockwell scale

Hardness is measured on the Rockwell C scale, HRC. A Tokyo retailer's glossary puts most Japanese knives at about HRC 58 to 64, with some very hard steels above that¹. Korin's rule of thumb is that softer steel sharpens more easily but dulls sooner, and harder steel holds its edge longer but takes longer to sharpen². Korin also says Japanese knives are generally lighter, thinner and harder than German ones. That suits precise work. It does not suit bones or frozen food².

If you cut left-handed

Read the listing twice. A single-bevel knife is ground for one hand, so a left-handed cook needs one made left-handed¹, and Korin says a right-handed blade cannot be converted². Expect to pay more. Wada Shoten, an old Sakai wholesaler, charges extra for left-handed deba and sashimi knives¹⁴. Check the handle as well, because D-shaped Japanese handles are usually made for the right hand¹. Many symmetrical double-bevel knives work in either hand¹.

Matching the knife to the cook

• One knife for a Western kitchen. A double-bevel gyuto, or a santoku if you prefer a shorter blade²¹.
• A vegetable-heavy kitchen. Add a nakiri for push-and-pull chopping³.
• Little time for upkeep. Stainless, or stainless-clad carbon steel¹³.
• The keenest edge, and you will dry it as you go. Carbon steel such as Shirogami or Aogami⁵.
• Sashimi and whole fish. A single-bevel yanagiba and deba, ground for your hand². For a first yanagiba, Korin suggests something forgiving, such as stain-resistant Ginsan or an easier-to-sharpen white steel².

Some makers cover the whole range and some pick one lane. Masamoto in Tokyo sells Japanese-style and Western-style knives, including a molybdenum stainless line¹². Sakai Takayuki makes Japanese, Western and Chinese shapes¹⁰. Kei Kobayashi in Seki works only in SG2, R2, powder stainless¹³. For the reasons behind the hype, read why Japanese knives are different. For where the shapes came from, read a short history. To decode the characters on the blade, see how to read a mei.

Whichever knife you buy, the Tsukiji shop Aritsugu gives the same instructions. Wash it by hand after use. Dry it well. Keep it out of the dishwasher. Before it goes into a drawer for a long stretch, give it a coat of oil. Aritsugu suggests camellia⁹.

Sources

Pages the editors read for this column, as fetched on 17 October 2026. Retailer and forum pages are secondary sources and are labelled as such in the text. Statements we could not confirm were left out. Links to Hocho Knife, a shop we have an affiliate relationship with, are marked sponsored (disclosure).

1. Tenpos Chef's Knives (retailer, Tokyo/Osaka), Japanese knife glossary (Japanese). tenpos-chefsknives.com/ja/glossary-ja/
2. Korin (retailer, New York), "Japanese Knife FAQ". korin.com/japanese-knife-faq
3. Knifewear (retailer, Canada), Fujiwara Maboroshi Nakiri 150mm product page (shape and care notes). knifewear.com/products/fujiwara-maboroshi-nakiri-150mm
4. Korin, "About Japanese Knives". korin.com/about-japanese-knives
5. Korin, "Elements of Steel". korin.com/about-elements-of-steels
6. Proterial, Yasugi Specialty Steel: GIN 3 data sheet and YSS grade list. proterial.com/e/yss/search/gin3.html
7. Aoyama Square (Japan Traditional Crafts Center), 堺打刃物 (Sakai uchihamono). kougeihin.jp/craft/0710/
8. Jikko (Sakai maker), "本焼包丁" (honyaki knives). jikko.jp/c/knowledge/detail/kouzou/honyaki-knife
9. Aritsugu (Tsukiji, Tokyo), FAQ: care. aritsugu.jp/%E3%82%88%E3%81%8F%E3%81%82%E3%82%8B%E3%81%94%E8%B3%AA%E5%
10. Aoki Hamono Seisakusho (maker of Sakai Takayuki), company profile. aoki-hamono.co.jp/company/
11. Hocho Knife (retailer), Sakai Takayuki brand page (product list). hocho-knife.com/sakai-takayuki/
12. Masamoto Sohonten, official site (product categories and news). masamoto-sohonten.co.jp/
13. Hocho Knife (retailer), Kei Kobayashi brand page. hocho-knife.com/kei-kobayashi/
14. Otonami, Wada Shoten (Sakai wholesaler) knife-making experience: options and pricing. otonami.jp/experiences/wada-shouten/

Written by The JKI Editors from the sources above, in our own words. Spotted an error? Email [email protected] and we will correct it.