Hardness is the number nobody publishes
Look at how blade blanks are sold. "Heat treated." "Hardened." "Consistent hardness." Almost nobody tells you the actual number.
That number matters more than the steel name. A soft M390 blade will underperform a properly hardened 1.4116, and there is no way to tell them apart by looking. Hardness is where heat treatment either succeeded or quietly failed, and it is the one specification that gets left off the page.
We publish ours. Here is what the number means and how to read it.
What HRC actually measures
HRC stands for Hardness Rockwell C. The test is simple: a diamond cone is pressed into the steel under a set load, and the depth of the dent is measured. Less depth, harder steel, higher number.
Knife blades live between roughly 54 and 65 HRC. Below 54 the edge folds under normal use. Above 65 it chips instead of bending, and sharpening becomes a specialist exercise.
Two points of HRC sound small and are not. The difference between 58 and 60 is clearly noticeable in edge retention, and equally noticeable when you sit down to sharpen.
The trade-off nobody escapes
Harder steel holds an edge longer. Harder steel is also more brittle, and harder to sharpen. That trade is unavoidable — heat treatment moves you along the line, it does not remove the line.
Which means there is no "best" hardness, only a hardness suited to a job:
- A camp knife that will be batoned wants toughness. Chipping in the field is worse than dulling in the field.
- A kitchen knife on a wooden board can be run harder. It is not being pried with, and the reward is an edge that lasts through weeks of prep.
- A hunting knife sits in between, and corrosion resistance matters as much as hardness.
Our steels and their hardness
Every figure below is what we actually run, confirmed for our own blades — not a range copied from a datasheet.
1.4116 — 54 to 57 HRC
The most forgiving steel we offer. Excellent corrosion resistance, sharpens easily on almost any stone, and takes abuse without chipping. It will not hold an edge as long as the harder steels, and it is not trying to. For a first knife, a working kitchen knife, or a blade that will live in a damp environment, it is a sensible choice.
N690 — 58 to 60 HRC
The all-rounder. Stainless, tough, holds an edge well, and still sharpens on ordinary equipment. Our kitchen profiles in N690 run at 58 to 59; outdoor profiles go a touch higher. If you want one steel that does most things well, this is it.
AEB-L — 60 HRC
A fine grained stainless steel that takes an exceptionally keen edge. The grain structure lets it go thinner at the apex than most steels of the same hardness, which is why it has a following among kitchen knife makers. Good corrosion resistance and easier to sharpen than its hardness suggests.
Sleipner — 60 to 62 HRC
Trades some corrosion resistance for wear resistance. Holds an edge notably longer than N690 and stands up to hard use. Our kitchen profiles run 60 to 61, and some are available with a stonewash finish. Not fully stainless — wipe it dry.
Elmax — 60 to 61 HRC
A powder metallurgical steel: excellent edge retention and excellent corrosion resistance at the same time, which conventional steels struggle to deliver together. Harder to sharpen than N690, and worth the trouble if you would rather sharpen rarely.
Vanax — 60 HRC
Nitrogen alloyed powder steel with the best corrosion resistance of anything we offer — genuinely at home in salt water. Edge retention is excellent. If your knife will see marine use or constant moisture, this is the one.
M390 — 60 to 61 HRC
The benchmark premium powder steel. Very high wear resistance, very good corrosion resistance, and the edge retention that made its reputation. Demands diamond or ceramic abrasives when it does finally need sharpening.
Vanadis 4 Extra — 63 to 64 HRC
The hardest blade we make. Outstanding edge holding and, unusually for something this hard, good toughness thanks to the powder metallurgical structure. It is not a beginner steel: sharpening requires diamond abrasives and a steady hand, and it is not stainless.
Quick comparison
| Steel |
HRC |
Type |
Best for |
| 1.4116 |
54–57 |
Stainless |
First builds, easy maintenance |
| N690 |
58–60 |
Stainless |
All-round use, kitchen and outdoors |
| AEB-L |
60 |
Stainless |
Kitchen knives, very fine edges |
| Sleipner |
60–62 |
Tool steel |
Hard use, long edge life |
| Elmax |
60–61 |
Powder stainless |
Edge retention with corrosion resistance |
| Vanax |
60 |
Powder stainless |
Marine and wet environments |
| M390 |
60–61 |
Powder stainless |
Premium EDC and kitchen |
| Vanadis 4 Extra |
63–64 |
Powder tool steel |
Maximum edge retention |
Why powder metallurgy changes the maths
Conventional steel is cast, and the carbides — the hard particles that resist wear — form in large, unevenly distributed clusters. Powder metallurgical steel is made by atomising molten steel into fine powder and consolidating it under heat and pressure. The carbides end up small and evenly spread.
The practical result: a powder steel can be run harder without becoming as brittle, and it takes a cleaner edge because there are no large carbides at the apex to tear out. Elmax, Vanax, M390 and Vanadis 4 Extra are all powder steels, which is why they appear high on the hardness list without a toughness penalty to match.
These four also receive a cryogenic step during heat treatment — cooled well below freezing after quenching, to convert retained austenite that would otherwise soften the blade over time. It is a step that only matters for these steels, and we apply it only where it belongs.
How we get the number we publish
Our blades are heat treated at Voestalpine — the mill that produced the steel in the first place — in industrial vacuum furnaces. Not in our workshop, not in a small shop oven.
That is the reason we are willing to print a hardness figure. Vacuum furnaces hold temperature across the whole load, there is no scale or decarburisation, and the process is documented. A batch comes back at the hardness it was specified for, and the next batch does too.
The full story of why we send blades back to the mill is here.
Choosing a number
If you are unsure, 58 to 60 HRC in a stainless steel covers most needs and forgives most mistakes. N690 sits exactly there.
Go harder when edge retention genuinely matters to you and you own the equipment to sharpen it. Go softer when the knife will be used roughly, or when you want to be able to touch it up on whatever stone is to hand.
And whichever way you go, ask for the number. A supplier who cannot tell you the hardness of a blade may not know it.
You can see the hardness figure on every product page in our blade blank range. If you want a steel recommendation for a specific job, our guides on kitchen knife steel and outdoor and EDC steel go deeper.