The Japanese Knife Steel Guide
Every steel that matters in Japanese kitchen knives: what it is, how hard it runs, who makes it, who uses it, and when it entered the story. Each steel links to a full reference page.
Steel is a set of tradeoffs
No knife steel wins everything. Harder steels hold an edge longer but chip more easily and take longer on the stones. Carbon steels feel magical to sharpen and cut, but they rust without care. Stainless gives up a little keenness for a lot of convenience. Powder metallurgy refines the grain so a steel can push both hardness and retention further.
Two rules before the table. First, heat treatment matters as much as the grade: the same VG-10 can be excellent or mediocre depending on the maker's furnace discipline. Second, the brand on the blade is not the steel: check the core. Our knife finder can shortcut the choice; the table and timeline below give you the full picture.
All steels, side by side
| Steel | Mill / Owner | Type | Carbon % | Typical HRC | Edge Retention | Toughness | Corrosion Res. | Ease of Sharpening | Best For |
|---|---|---|---|---|---|---|---|---|---|
| AUS-8 | Aichi Steel | Stainless (ingot) | 0.70-0.75 | 58-60 | Medium | High | High | Very high | First Japanese knife, easy care (Okami Classic) |
| AUS-10 | Aichi Steel | Stainless (ingot) | 1.00-1.10 | 60-61 | Med-High | Medium | High | High | Damascus value tier (Okami Premium) |
| VG-10 | Takefu Special Steel | Stainless (ingot, Co) | 0.95-1.05 | 60-62 | High | Medium | High | Medium | The mainstream premium standard |
| VG-MAX | Kai (proprietary) | Stainless (VG-10 derivative) | not published | 60-61 | High | Medium | High | Medium | Shun lines |
| Ginsan (Silver 3) | Proterial (Hitachi) | Stainless (fine grain) | 0.95-1.10 | 60-62 | Med-High | Medium | High | Very high | Stainless that sharpens like carbon |
| Shirogami (White) | Proterial (Hitachi) | Carbon | 1.05-1.40 by grade | 61-64 | Med-High | Medium | Low | Very high | Purist edges, traditional knives |
| Aogami (Blue) | Proterial (Hitachi) | Carbon (W, Cr) | 1.05-1.40 by grade | 61-65 | High | Medium | Low | High | Craft forges, kurouchi work |
| Aogami Super | Proterial (Hitachi) | Carbon (W, Cr, Mo, V) | 1.40-1.50 | 64-66 | Very high | Low-Med | Low | Medium | Peak carbon performance |
| SG2 / R2 | Takefu (powder) | Stainless PM | 1.25-1.45 | 62-64 | Very high | Medium | High | Low-Med | Premium powder mainstream |
| SPG STRIX | Takefu (powder) | Stainless PM | not published | 63-65 | Very high (early reports) | reported improved | High | reported easier than SG2 | The new generation, still proving itself |
| ZDP-189 | Proterial (Hitachi, powder) | Stainless PM (extreme) | ~3.0 | 64-67 | Extreme | Low | Medium | Low (diamond stones) | Collectors, specialists |
| CROMOVA 18 | Yoshikin (Global) | Stainless (proprietary) | not published | 56-58 | Medium | High | High | Very high | Global's all-steel design |
| FC61 | Zwilling (Miyabi) | Stainless (AEB-L class) | ~0.60-0.65 | ~61 | Med-High | High | High | High | Miyabi entry and mid lines |
| MC66 | Zwilling (Miyabi) | Stainless PM (ZDP class) | ~3.0 (reported) | ~66 | Extreme | Low | Medium | Low | Miyabi Black flagship |
Ratings are Okami's editorial assessment from mill data and published analyses, assuming competent heat treatment. "Not published" means the owner discloses no composition. HRC windows are typical retail implementations, not spec maximums.
When each steel entered the story
From the tatara furnaces behind the 1899 Yasugi works to Takefu's newest powder steel in 2023. Dates marked approximate or uncertain reflect honest gaps in the public record: several famous steels have no documented introduction year, and we refuse to invent one.
Compiled by Okami from mill materials (Proterial, Takefu Special Steel, Aichi Steel), maker disclosures, and published steel analyses. Where sources conflict, we show a range and flag confidence.
Which steel is for you
- First Japanese knife, zero fuss: AUS-8, FC61, or CROMOVA 18. Forgiving, stainless, easy on any stone.
- Best all-round value: AUS-10 or VG-10. Real performance, sane sharpening, wide choice of makers.
- Maximum edge retention, still stainless: SG2 / R2, or watch SPG STRIX as it proves itself.
- The traditional experience: Shirogami for purist keenness, Aogami for retention with soul, Ginsan if you want that feel without the rust.
- The deep end: Aogami Super and ZDP-189. Spectacular edges, real demands on skill and care.
Where Okami sits
The Okami Classic runs AUS-8 at 58-60 HRC for $149.99; the Okami Premium runs an AUS-10 core in 67-layer Damascus at 60-61 HRC for $199. Both were chosen for performance per dollar, and everything above is here so you can judge that choice against the whole field.
Steel questions, answered
What is the best steel for Japanese kitchen knives?
There is no single best steel, only best fits. For a first knife, forgiving stainless like AUS-8 or FC61 is ideal. For edge retention, powder steels like SG2 lead. For the keenest feel on the stones, carbon steels like Shirogami and Aogami are unmatched, at the cost of rust care. Heat treatment quality matters as much as the grade.
What is the difference between carbon and stainless knife steel?
Carbon steels (Shirogami, Aogami) contain little or no chromium, so they take extremely keen edges and sharpen easily but rust without care. Stainless steels add roughly 13 percent or more chromium for corrosion resistance. Powder metallurgy steels (SG2, SPG STRIX, ZDP-189) refine the microstructure for hardness and retention.
Which steel does Okami use?
The Okami Classic uses AUS-8 by Aichi Steel at 58-60 HRC ($149.99). The Okami Premium uses an AUS-10 core in 67-layer Damascus cladding at 60-61 HRC ($199). We chose both for honest performance per dollar rather than marketing prestige.
What does HRC mean for knives?
HRC is the Rockwell C hardness scale. Most Japanese kitchen knives run 58 to 66 HRC. Higher numbers hold an edge longer but are more brittle and slower to sharpen; lower numbers are tougher and easier to maintain.
What is the newest Japanese knife steel?
SPG STRIX, introduced by Takefu Special Steel in late 2023, is the newest mainstream Japanese cutlery steel. It is a powder metallurgy stainless reported around 63-65 HRC, designed for SG2-class edge retention with easier sharpening.
Is Damascus steel better?
The visible Damascus pattern is cladding; the core steel does the cutting. Damascus adds protection and beauty, not sharpness. Judge a Damascus knife by its core steel and heat treatment, not its layer count.
Sources
Proterial (Hitachi Metals) Yasuki specialty steel data, Takefu Special Steel materials, Aichi Steel specifications, Kai and Zwilling brand disclosures, Yoshikin materials, and published independent steel analyses. Compiled and assessed by the Okami editorial team.
