Japanese Kitchen Knife Steel: A Guide for Beginners

Japanese Kitchen Knife Steel: A Guide for Beginners

When it comes to Japanese kitchen knives, the quality of the steel used in their construction can make all the difference in terms of performance, sharpness, and overall durability. Understanding the various types of steel used in Japanese knives can be a bit overwhelming for beginners, but with the right knowledge, you can make an informed decision when choosing your next knife.

In this guide, we'll provide an overview of the most common types of steel used in Japanese kitchen knives, as well as their respective properties, advantages, and disadvantages.

There are three general types of steel that are common in Japanese Cutlery:

  • CLAD - Carbon & Stainless


Named for the colored paper attached to the steel at the HITACHI factory in Japan, carbon steel knives are not rust-resistant and must be kept clean and dry when not in use. A light layer of blade (Tsubaki) oil will help protect the blade from rust, especially in humid climates. Carbon steel is easy to sharpen and forms a terrific edge. If properly cared for, carbon steel will form a beautiful patina over time but if neglected, they can rust.

White Paper (Shirogami) Steels

This is a very pure form of carbon steel that oxidizes faster than blue steel but is easier to sharpen and creates a terrific edge.

There are three types or grades of Shirogami steel:

  • Shirogami #1 - The hardest white paper steel. It will stay sharp the longest but can be a tad brittle under aggressive use.
  • Shirogami #2 - Most commonly used type of white steel. Good edge retention and very easy to sharpen.
  • Shirogami #3 - The most durable of the three types, but it will dull more quickly.

Blue Paper (Aogami) Steels

Blue steel is essentially white paper steel in which Chromium (Cr) and Tungsten (W) have been added. These alloys allow for blue steel to be harder than white steel. Blue steel is also reactive, but less than Shirogami. Designed for knives and tools, this steel has supreme edge retention while remaining easy to sharpen.

Blue paper steel also has three grades:

  • Aogami Super - Vanadium (V) is added to make this steel super strong and hard. Top-notch edge retention for carbon steel with great wear resistance.
  • Aogami #1 - Less common than #2 and Super, but forms a terrific edge that stays sharper longer than #2.
  • Aogami #2 - The most durable of the blue steels. A tough steel that sharpens easily.

Yellow Paper (Kigami) Steels

Much less common in high-grade Cutlery, but it is often used for tool making and agricultural products like sickles, hatchets, and axes.


These steels have a much lower carbon content and contain at least 10.5% Chromium (Cr). Although generally a little harder to sharpen than high carbon knives, stainless steel knives are much more rust-resistant and they are very easy to maintain. They contain many more alloys such as Molybdenum (Mo), Vanadium (V), Nickel (Ni), and Cobalt (Co) to form a wide variety of steels suitable for both beginners and professionals.

Molybdenum Vanadium Steel

A common type of stainless steel that is of good quality. Very durable steel that is great for beginners and people who are rough with their knives. Easy to re-sharpen but will need to be re-sharpened more quickly than other varieties.

VG-10 Steel

This is the most commonly used stainless steel in Japanese cutlery due to its good edge retention and moderate ease of sharpening. The addition of cobalt (Co) adds toughness and durability, while a high vanadium (V) content gives the steel high rust resistance. VG-10 steel is often used in Damascus and Migaki style blades.

AUS-8 & AUS-10 Steel

These steels have less chromium (Cr) than VG-10, making them less rust-resistant. However, nickel (Ni) adds to their toughness and durability, making them a great middle ground between edge formation and retention.

High Speed Powdered Steels - R2, SG2, SRS-15

These steels are called "powdered" steel because of their very fine grain structure, which allows for excellent edge formation. They are extremely hard steels with the longest edge retention of any stainless steel, but are harder to sharpen. They are ideal for professionals who demand the best from their cutlery. High speed powdered steels like R2, SG2, and SRS-15 are also used for the rails of high speed trains and drill bits.

Gin-san Steel - Gingami #3

This is a special HITACHI steel that functions similar to a semi-stainless steel. It has more rust resistance than high carbon steels, but less than most stainless steels. This steel forms a terrific edge with the durability of a stainless steel but with the ease of sharpening that is similar to harder high-carbon steels.

Clad Steel

Clad steel knives contain both high carbon and stainless steels, typically with a core of Shirogami or Aogami steel and outer layers of stainless or low-carbon steel. These blades are popular because users gain the advantage of a carbon edge that is easy to sharpen and forms a terrific edge, while not having to worry about oxidation issues across the entire blade. There are two techniques for achieving clad steel: San-mai, where a hard carbon core is forge laminated with two thin layers of stainless steel throughout the entirety of the blade, and Warikomi, where one piece of stainless steel is heated and folded around the carbon core, leaving the carbon exposed on the edge side but disguised on the spine side.

        When choosing the right steel for your Japanese kitchen knife, consider your personal preference and how you plan to use the knife. Carbon steel is a good choice if you want a knife that is easy to sharpen and holds an edge well, while stainless steel is a better option if you want a knife that requires less maintenance and is rust-resistant. Damascus steel is a good choice if you're looking for a knife that is both beautiful and durable.

No matter which steel you choose, proper care is essential for ensuring the longevity and performance of your knife. This includes regular sharpening, cleaning and drying after each use, and storing it in a dry place away from moisture.

         In conclusion, understanding the various types of steel used in Japanese kitchen knives is essential for making an informed decision when choosing a knife that best fits your needs. With the right knowledge and proper care, your Japanese knife can become an essential tool in your kitchen for years to come. And whenever you need to change handles for your knife you could check out our service of custom knife handle made at the traditional Japanese way at boogwa.com.

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