How to Measure Quality of the Steel for any Knife?

How do you know if steel is of high quality?

If you’re paying 300-400$ – for a knife you can assume is a quality. But you can also get a quality steel for under 100 $ so how would you know?

We’re going to talk about few important ways that steel is quality is measured.

And there are tons of ways that you can measure steel quality, you talk edge retention, its grips, hardness .its harden ability, its tensile ability, yield strength and the list goes on and on.

In each industry focuses on different things. In for example drilling steel wouldn’t be good for cutlery steel and knife making.

Generally speaking knives don’t get super-hot. You don’t have to worry about their hotness and hardness. Failing at X number of degrees

Things we are going to talk about that we think are very important

  • Strength – what it means to have strong knife blade
  • Corrosion resistance – that’s important depending what you want to do
  • Heat treatment – which is something that usually never talked about


When someone talk about steel that’s strong. Their talking about hardness of the steel and toughness. And these are two different things

Hardness basically measures metal resistance to penetration, the way you measure is with Rockwell tester.

Most good knifes give Rockwell number from high 50 to low 60s.

The next part of strength is toughness, and basically what it means the blade is resistant to being fractures. If a knife has high toughness it means that it will be very hard to break that blade.

Another way is to view is flexibility. When you have a blade has high toughness, the cutting edge will be extremely thing but it will also extremely resistant. If you have tough thin blade sharpening is also much easier than other blade types.

At this point you might be wondering, can I just buy a knife that is hard and tough. If you make a stelel harder you reduce its toughness, and opposite is also true.

You an have a knife which is incredibly tough, but if you drop it on hard surface it will shatter. And you can have a knife that is hard but you’ll have to sharpen it every time you use it.

Corrosion resistance.

It’s mentioned that there are no tool and blade that is impervious to corrosion. Regardless of chromium percentage, regardless what knife manufactures says, it could corrode, it could rust.

Some steels that are corrosion resistant 440c s30b those two are considered really highly corrosion resistant. The thing about corrosion resistance, if you take good care of your knife you shouldn’t have problems with it. If you spend a lot of time in corrosive environments, cutting things that are acidic, if you spending a lt of time in salt water you might want to find knife that has better corrosion resistance than others.

Heat Treatment.

If you ever bought a stainless steel tool, and find that it’s corroded later on. Chances are that that happened because it wasn’t properly heat treated.

You can’t ever know how the blade is heat treated unless someone makes it for you.

Most knife sellers buy steel from steel producers, and steel producers don’t share exact features of process. Basically if you own a knife company you goal is to make a profit, so you’re going to do business with lowest bidder.

Cheap piece of steel that is properly heat treated can easily outperform expensive steel which was improperly heat treated.

Infographic by Blades HQ