Japanese knife steel names look like a code at first: VG-10, SG2, Aogami Super, Shirogami #2, Ginsan. Once you know that they fall into three families and come from a handful of Japanese mills, the code is easy to read. This page covers the eight steels we carry, compares them in one table, and links to a separate page for each.
We buy these knives in Japan, where the steel is the first thing a shop clerk tells you about a blade. It is worth understanding, but it is not the only thing that decides how a knife cuts. More on that near the end.
The three families
Carbon steel is iron plus carbon with very little else. It takes the sharpest, most refined edge and is the easiest to sharpen, but it rusts if left wet and reacts with acidic food. In Japan the main carbon steels come from Hitachi (now Proterial) and are named by the color of the paper they were originally wrapped in: Shirogami (White) and Aogami (Blue).
Stainless steel adds enough chromium to resist rust. It is more forgiving in a home kitchen. Modern Japanese stainless steels such as VG-10 get much harder and sharper than the stainless in most Western knives.
Powder stainless is made by atomizing molten steel into fine powder and pressing it back together. The result is a very fine, even structure that can be pushed to high hardness without becoming coarse. SG2/R2 and ZDP-189 are in this group. They hold an edge a long time but take more work to sharpen.
There is also a middle ground. Some stainless steels, Ginsan being the best example, behave so much like carbon steel on the stone that Japanese makers treat them as a stainless alternative for traditional knives. And many carbon knives are clad in stainless on the outside, so only the edge can rust.
The eight steels at a glance
Ratings are relative to each other on a 1 to 5 scale, not absolute. A 3 for rust resistance is still a stainless steel you can leave on the board for a while.
| Steel | Kind | Maker | Typical HRC | Edge retention | Ease of sharpening | Rust resistance |
|---|---|---|---|---|---|---|
| VG-10 | Stainless | Takefu Special Steel | 60 to 61 | 3 | 4 | 5 |
| SG2 / R2 | Powder stainless | Kobelco | 62 to 64 | 4 | 3 | 4 |
| ZDP-189 | Powder stainless | Hitachi | 65 to 67 | 5 | 1 | 4 |
| AUS-10 | Stainless | Aichi Steel | 58 to 60 | 2 | 4 | 5 |
| Ginsan (Silver 3) | Stainless | Hitachi | 60 to 62 | 3 | 5 | 4 |
| Shirogami #2 | Carbon | Hitachi | 61 to 63 | 2 | 5 | 1 |
| Aogami #2 | Carbon | Hitachi | 61 to 63 | 3 | 4 | 2 |
| Aogami Super | Carbon | Hitachi | 63 to 65 | 4 | 3 | 2 |
HRC is Rockwell hardness. Most German kitchen knives sit around 56 to 58, so every steel here is harder than the knife you probably own now.
The steels one by one
VG-10. The most common core steel in Japanese stainless knives, made by Takefu Special Steel in Echizen. It hits 60 to 61 HRC, takes a sharp edge easily, and shrugs off a wet board. If you do not know which steel you want, start here. The Tojiro DP Gyuto 210 and the Sakai Takayuki Damascus Gyuto 210 both use it. Full page: VG-10 steel.
SG2 / R2. A powder stainless from Kobelco, sold under two names for the same steel. At 62 to 64 HRC it holds an edge noticeably longer than VG-10, and its fine structure takes a very clean polish. It is a step up for daily cooks who hate sharpening often. See the Takamura R2 Gyuto 210 and Yu Kurosaki Senko SG2 Gyuto 210. Full page: SG2/R2 steel.
ZDP-189. Hitachi’s powder stainless, usually run around 65 to 67 HRC. It has the longest edge life of anything on this list and is also the slowest to sharpen and the least tolerant of twisting or impact. It suits experienced sharpeners who want to go a long time between sessions. Full page: ZDP-189 steel.
AUS-10. A stainless from Aichi Steel, a little softer than VG-10 at around 58 to 60 HRC. That makes it tougher and less prone to chipping, with shorter edge life. It is a reasonable steel for heavy use and for people moving from German knives. Its sibling AUS-8 is softer again and shows up on budget knives. Full page: AUS-10 steel.
Ginsan (Silver 3). A Hitachi stainless with a very fine grain, around 60 to 62 HRC. It sharpens almost like carbon steel, which is why makers in Sakai use it for traditional knives such as nakiri and yanagiba when a customer wants less maintenance. The Sakai Takayuki Ginsan Nakiri 165 is a good example. Full page: Ginsan steel.
Shirogami #2 (White #2). The simplest Hitachi carbon steel, around 61 to 63 HRC. It gets extremely sharp on the stone very quickly, which is why many traditional smiths love it. The edge dulls sooner than Aogami, and it rusts fast if neglected. It is used in the Sakai Takayuki Shirogami Deba 165 and the budget Tojiro Shirogami Nakiri. Shirogami #1 has more carbon and is harder but more brittle. Full page: Shirogami #2 steel.
Aogami #2 (Blue #2). White steel with chromium and tungsten added. It holds an edge longer than Shirogami and rusts a bit more slowly, while still sharpening easily. Many cooks find it the best balance among carbon steels. Aogami #1 carries more carbon and runs a little harder. Full page: Aogami #2 steel.
Aogami Super (Blue Super). The top of the Aogami range, with more carbon plus molybdenum and vanadium, typically 63 to 65 HRC. It keeps an edge the longest of the carbon steels here. It needs more time on the stone than Shirogami and still rusts like carbon steel. The Moritaka Aogami Super Bunka 170 uses it. Full page: Aogami Super steel.
Cladding changes the daily experience
Most Japanese knives are not one piece of steel. A hard core forms the edge and is sandwiched between softer outer layers (san-mai construction). The outer layers can be stainless, soft iron, or a patterned Damascus stack.
This matters for care. A carbon core with stainless cladding only rusts at the exposed edge, so it is far easier to live with than a fully carbon blade. A carbon core with iron cladding and a kurouchi finish, common in Tosa and Echizen, will rust anywhere it stays wet. Always check both the core and the cladding. Damascus Japanese knives explained covers the patterned kind.
Hardness is not the whole story
Two knives in the same steel can feel very different. The smith’s heat treatment decides the final hardness and how tough the edge is. The grind decides how thin the blade is behind the edge, which affects cutting feel more than steel does. A thin VG-10 knife will cut a carrot more easily than a thick Aogami Super one.
So treat steel as one input. Use it to decide how much care you want to give and how often you want to sharpen. Then choose the maker, shape and grind.
How to pick a steel
If you want low maintenance and have never sharpened on a stone, choose VG-10 or Ginsan. Both sharpen easily and neither will surprise you with rust.
If you cook every day, already sharpen, and want fewer sharpening sessions, choose SG2/R2. Go to ZDP-189 only if you enjoy sharpening and have good technique.
If you want the sharpest possible edge and like the idea of a knife that changes color with use, choose carbon. Start with Shirogami #2 or Aogami #2, and move to Aogami Super once you know you enjoy it. Read carbon steel vs stainless Japanese knives and how to care for a carbon steel knife before you order.
If you are coming from German knives and worry about chipping, AUS-10 or VG-10 are the gentlest step. Japanese vs German knives explains the differences in handling.
For traditional single-bevel knives, choose Shirogami if you will keep it dry, or Ginsan if you want it easier. Whatever you pick, learn to use a stone. How to sharpen a Japanese knife on a whetstone covers it step by step, and our shortlist of the best Japanese kitchen knives shows these steels in actual products.
If you already have a shape in mind and just want to know which steel fits your habits, ask us on the request page and we will suggest a couple of options in your budget.
Frequently asked questions
What is the best steel for a Japanese kitchen knife?
There is no single best. VG-10 is the easiest all-round stainless, SG2/R2 holds an edge longer, and Shirogami or Aogami carbon steels get the keenest edge but need to be kept dry.
Is higher HRC always better?
No. Higher hardness holds an edge longer but makes the edge more brittle and slower to sharpen. Heat treatment and grind matter as much as the number on the label.
What is the difference between Aogami and Shirogami?
Both are Hitachi carbon steels. Shirogami (White) is the simpler, purer steel that sharpens fastest, while Aogami (Blue) adds chromium and tungsten for longer edge retention and slightly slower rusting.
Are SG2 and R2 the same steel?
Yes. SG2 and R2 are the same powder stainless steel sold under two names, so a knife labeled either way should behave the same for the same heat treatment.