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Video
Here is the video version of the following information:
Can You Even Tell the Difference?
I have seen a common comment on knife forums and on my YouTube videos. It seems to be one of those statements that different people unintentionally copy from someone else. Everyone seems to think they thought of it on their own. It has a lot of variations but boils down to one statement: “People can’t tell the difference between knife steels anyway.”
The reason why the variations matter is because people are making different points when saying it. I believe that these kinds of statements started out as a criticism of certain knife buyers: “You never use your knives so you wouldn’t know what knife steel was even used.”
Another variation is to say that “premium” knife steels are all good and the differences between them are so small that nitpicking about which one is used is unimportant.
But I have seen people take this statement to the extreme and claim that there actually is no real difference between steels at all.
Edge Retention
This discussion can go a lot of different ways so let’s start with one of knife enthusiasts favorite topics – edge retention. If we look at the CATRA chart for different steels, for example:
Those tests were all done with identical edge geometry. You can also see the approximate effect of hardness by looking at the dashed diagonal lines (some steels were also tested at multiple hardness levels). You will notice that there are steels that tested under 300 mm of cardstock cut, all the way up to 1150 mm. That is a huge range. If we compared 8670 and Rex 121 in virtually any side by side slicing test with identical edge geometry I find it hard to believe that someone wouldn’t see the difference.
The Car Analogy – Commuter vs Soccer Parent
But most knife users are not doing side by side tests to compare steels. And that’s fine. When we cut random things, a random amount per day (or week, or month) it is very difficult to know how much cutting one knife did vs another. It’s like if I was comparing the gas mileage of two cars. If I was a commuter making the same drive to and from work five days a week and not driving my car at any other time, the comparison would be obvious. I may not even need to run any numbers to know if one car had only 20% better gas mileage, much less 100% better. However, if it is a family car, being driven around for different kids activities, sometimes going to the store, sometimes sitting for two days, etc. it would be very difficult to be able to tell if one car had 20% better gas mileage than another. The usage would be too variable. That doesn’t mean that I’m not actually getting better gas mileage out of one of the cars. It just means that I would have to look at some numbers to find out. (Where this analogy partially falls down is that our cars do show us the average MPG where the knife does not have a record of how much it cuts in between resharpening).
The point I am making is that just because someone couldn’t tell that there was a difference doesn’t mean that there wasn’t a difference. A knife can be cutting longer even if you didn’t notice. That also doesn’t mean that you have to buy a new knife any time there is a new knife steel. Just like you don’t need to buy a new Honda Accord just because they redesigned it for 2026. Engineers make improvements to products, and progress will continue.
Differences within Category
However, I can also agree that there is a level of nitpicking that can be unproductive among knife enthusiasts. This is especially true when people are arguing about minute differences between steels within the same “category.” For example, comparing the edge retention of S30V and M390. The differences are going to be small. There would be little difference to select one knife over another if the main goal was to achieve a small percentage increase in edge retention by selecting M390. That is partially ignoring other tradeoffs between them, of course. But they are both powder metallurgy stainless steels with 4% vanadium with similar edge retention. They are in the same “category.” Sometimes there are improvements with new steels within a given category, or at least a different set of tradeoffs that could be more desirable for different applications. But usually we are not talking about massive differences.
If, however, we are talking about 8670 vs S125V, yes, these steels are massively different. Simple low alloy steels used by forging bladesmiths vs a high wear resistance stainless steel by a stock removal maker would not be the same. These are totally different categories and will behave very differently in many ways. Calling these differences indecipherable would be nonsensical.
Edge Geometry
Steel is only one part of the equation. Every knife buyer knows that different knives can perform very differently even in the same steel. Even if they had identical heat treatments. Because edge geometry is the most important factor for knife performance.
When pure cutting performance is desired, thin, acute edges are king. It makes an even bigger difference than the steel or heat treatment. You can see that the “cheap” AUS-6 with low wear resistance can cut just as long as the high wear resistance S110V. That is if the AUS-6 is at 12.5 dps (25 total degrees) and the S110V is over 20 dps.
So this is another case where knife buyers may be confused about what the real effect of steel is. They might have one knife in a “super” steel that doesn’t cut very well and doesn’t cut very long all because the knife has a thick edge. Then another knife in a common steel that cuts great and keeps cutting. They conclude that the steel type must be nothing but hype.
Toughness
Big chopping knives and axes generally require thicker, more obtuse edges to handle abuse. Below I have images of AEB-L knives that I tested with controlled impacts at 15 dps vs 25 dps. With the 15 dps edge it only took 0.31 ft-lbs to generate a good size chip, and 1.36 ft-lbs to completely blow out the edge. With 25 dps with the same 1.36 ft-lbs there was just a minor ripple.
So just like with edge retention, the edge geometry is going to be most important, before steel type or heat treatment. However, there are real differences in toughness between different steels. Some are more prone to chipping and breaking than others:
I have definitely seen more broken Spyderco knives in high hardness Maxamet and Rex 121 than I have in higher toughness steels. That is the tradeoff. Engineering is all about tradeoffs. If you want the ultimate in wear resistance you will no longer have the ultimate in toughness. Some steels will have a higher wear resistance for a given level of toughness, but there will never be a magic steel that is perfect in every category. This is another of the many reasons why you can’t just say that there is no difference between steels. The right steel should be chosen for the right knife and the right buyer/user.
Toughness is one of those properties where you have enough of it until you didn’t. Either the toughness was sufficient for the task and there was no chipping or breaking, or the knife failed. So there can always be a debate as to whether how much toughness is enough. Because that will change based on the edge geometry and how the knife is being used.
Hardness
Hardness is less a reflection of steel type than it is of heat treatment, but there are still ranges. Some steels can’t go any higher than 60 Rc or even lower. Some steels like the “super” high speed steels can go all the way up to 70 Rc. Hardness is another of the places where I see people misinterpret steel properties, especially when it comes to relatively soft steel. Knives with soft steel will almost always deform rather than chip. This is sometimes misinterpreted as the steel having high “toughness.” If a knife edge deformed it failed due to insufficient strength, not because it was high in toughness. For example, knifemaker Shawn Houston compared an ESEE in relatively soft 1095 and compared it with a MagnaCut knife with similar edge geometry but higher hardness. In the nail chop test the 1095 failed due to deformation while the MagnaCut did not. This was due to hardness, not toughness.
Corrosion Resistance
Stain resistance is one of the more obvious categories, I think, and is less debated. Stainless steels rust less than non-stainless steels. And there are some stainless steels that are better than others. For some buyers it is acceptable to keep their knives oiled and the environment and use isn’t a problem for corrosion. But in either case I think we can all agree that some steels (when heat treated properly) show better resistance to corrosion.
Sharpening
Another area where people generally tend to notice steel difference is in sharpening. However, even in this case it isn’t as simple as some people perceive. Edge geometry is also important for sharpening. Thin edges require very little material to be removed, so even high wear resistance steels aren’t much more work to sharpen. It also matters what abrasives are being used. I used very hard CBN abrasive in my CATRA knives when resharpening and there wasn’t much difference between 8670 and Rex 121 in terms of how much strokes were required to raise a burr. The mechanical removal of material was more the limiting factor. It also matters to what level of polish you are taking it to. Those CATRA knives were only being sharpened to 400 grit. Polishing to high grit levels, especially with softer abrasives, can take much longer with high wear resistance steels with hard vanadium carbides. Heat treatment is also a factor. I found that deburring and getting a crisp edge was challenging with steels that had high retained austenite. I don’t have the space to write about what retained austenite is here, but you can have high retained austenite in virtually any steel if it is heat treated improperly.
Summary
So there was my little rant about whether steels are all the same and no one can tell the difference. They are different. And even if you didn’t notice that doesn’t mean they weren’t different. There are a lot of factors that can control whether someone notices when one knife is outperforming another, with steel being only one of them. And the bigger factor might just be commenters trying to win points with their spicy opinions about steel choices.
It just makes sense to have a balanced steel for a edc knife. It’s good for everything. I do believe in specialty steels for specific uses, absolutely. My years of knife experience have led me to one steel for edc and that being magnacut. Not unless there is a better balanced steel out there that I don’t know about.
I toi have Magnacut in service. Wonderful steel. Thanks Larin!
Well said sir🔪🫡
This is a great synopsis. Thank you for putting this information out there in such a generalized form, yet with enough detail, to settle some of the discussions that I have had with Hunting Buddies. I have a number of different manufacturers and steals and different knife configurations.
What people don’t seem to understand is that each knife i have performs better in certain environments and tasks than others, especially based on what the task is.
Cant compare my elk hunting knife to the slicing kitchen knife, it’s just a ridiculous comparison.
Some of my buddies are knife steel snobs, others arw just cheap, and some whom have no clue what they’re talking about and have to keep sharpening their knives while boning out a single elk.
I typically have 3 very different knives in my hunt pack. One for skinning, one for the heavy breakdown of the carcass and the last for meat cutting.
Sometimes they mess with me for the 3 knife selection (which changes when antelope hunting or other tasks) but i very seldom have to sharpen a knife in the field and my knife configuration and .steel selection means I can go on several hunts or animals without sharpening or just a touch up. Advantage me!
It would be amazing if there was that one perfect Steel, but I doubt that will ever happen.
Thank you for a well thought out simple article that I am going to forward to some of my friends.
I’ve made a few knives mostly for personal use starting long before I became a metallurgical engineer. Now that I have some information, understanding, and a half century plus of experience, there is much less mystery and confusion. No doubt, steel and heat treat choice is huge. Two of my knives, one of O1 the other of M4 tool steels, have the same hardness. But they are on different planets in terms of edge holding! The differences are VERY real.
Retained austenite is indeed a huge problem and mostly never discussed. Because no one outside a metlab could measure and stratify, unfortunately.
As is with the italians (e.g. MKM) chronically undertreating M390 (58-60 HRC) as well as N690. Especially steels bearing a second hardening point I also never understood not going to that point. Or better chose a non marketing-steel instead…
well said, larrin!
i feel like the debates on the line between ‘nobody can tell a difference’ and ‘the new hyperchop 69-420X boosts 1.3% finer grain, i must replace all my knives’ frequently omit crucial points.
it’s very easy to overcommit to either side, while losing sight of the important point of ‘good enough’ for a given task at hand. plenty of everyday tasks have a very low bar of ‘good enough’ and a knife in a boring steel is perfectly adequate. it’s fair to say that as distance past that ‘good enough’ point increases, you’re getting less and less tangible or noticeable return for the improvements in steel performance, at this task.
this is neither an argument that continued steel development is pointless, nor is it an argument that everybody ought to be happy with the steel that was good enough for our grandfathers.
let alone that, as with any other hobby that’s built around things with a tool characteristic – think fountain pens, watches, etc – enthusiast interest will not only be focused on whether a thing is adequate (or even excellent) for a task, but also on nuances of the craft, history, and so on. think the prevalence of automatic watches when a quartz watch is a better timekeeping tool, or that some people desire to have very high end dive watches for substantial costs, without even being into diving.
when somebody is a knife nerd with a steel bend, having a knife made of a certain steel becomes itself desirable. not because there is a tangible use in it. and that’s no less legitimate a reason for wanting to have a knife in the latest super steel. but i feel like debates would be in a better space if we were more upfront about whether we’re buying a high performance product because it matches our use case or because we desire it for its coolness. or somewhere in between.
Great comments Raphael.
The steels and knives that I use in my 3 knife Elk hunting kit are there for specific reasons and have specific uses for the particular task of skinning, breaking down and boneing out the carcass abd cutting the meat. The meat cutting blade has a specific purpose and would be quite difficult to use when either skinning or breaking down the carcass, just like the large heavy bladed 3V steel knife is an good meat cutter but excellent for heavy cutting and breaking down. The smaller S30V skinning knife is designed for exactly that, while capable of doing the job of the 3V knife, the blade profile is designed for skinning. So all 3 steels are great steels, but the knife design has specific purposes and that is what sets them aside.
Yes, I could just carry the S30V knife or the 3V knife instead of all 3 blades, but why? A few extra ounces are not a big deal to me.
For EDC that is a totally different purpose and based on environmental factors like high humidity, fishing in both fresh or salt water or traveling that includes a lot of driving I will pack the appropriate knives. Driving with a 4 ” bladed folder in my pocket is adequate, however a shorter blade like a Para 3 size is perfect. A fixed blade always accompanies me in my bag.
Some will say that I am too concerned about what to carry and for what purpose, my philosophy has always been “be prepared” an include surprises, as you never know.
thanks, marc. 🙂
i’m fully with you – and i think your 3 knives instead of just one is a useful addition to what i wrote about ‘good enough’ (alas, it was a long comment already). i might have made it sound a bit too much like there was one such point for any given task, but that leaves out the many factors that inform it. your approach – a single ‘elk hunting’ task vs three specific subtasks – changes the equation substantially. (and if the father of ultralight backpacking, george washington sears, then a sexagenarian with tbc and asthma, could carry two knives and a two-bit hatchet on an >400 km solo canoe tour through the adirondacks, an elk hunter surely can carry three knives he gets good use out of.)
user capability is also a big factor. ‘sure, this tool is much better than what i am using, but how much of that potential would *i* be able to get out of it’ is something i ask myself quite a lot.
and, of course, enthusiast interest will totally extend to having a good choice for every variation of a task. 😉
Correct, we have so many more conveniences/luxuries today that an extra 10 or so ounces of tools that get the job done in a pack is nothing.
Besides, I have seen way too many bad cuts on people who use the wrong tool (aka knife suitable for the task), cheap steel requiring constant sharpening or folders that don’t have a blade locking system that is suitable for the task. I have seen people that also do not know how to use the Knife they have chosen, don’t realize the limiting factors that can be presented if inappropriate knives are used…..On an on….
Another GREAT article from Larrin.
Thanks for sharing.
I’ve been carrying a pocket knife daily for about 60 years and I use them every day. My first knife was small Case with carbon steel (my dad gave it to me and I loved it). I have noticed big differences in performance as steels have improved. Around 1971-72 I bought a Buck folding hunter. It was a massive improvement over my carbon steel knives. Fast forward to today, I bought a Spyderco Para 3 in 15v and it is simply amazing. I sharpen with diamond stones and finish with an ultra fine ceramic bench stone. I use the para 3 every day and it just doesn’t get dull enough to ever need the diamond stones. I touch it up every week or two on the ceramic and I can shave with it. I also notice differences in the “sharpenability” between steels. Using the same stones with my knives it seems like Cru Wear takes a finer edge than any other. 14C28N is another that gets screaming sharp but it dulls quickly. I think my experience with my knives in S30v, S35vn, Cru Wear, and good old Buck 440c over decades matches pretty well with what you show in your charts. (I have 2 knives in Magnacut now, but I haven’t used them yet.)
I really enjoy your work and it is a big help in purchasing knives for specific uses. Thanks for all you do.
Having been around the block on steel, sharpness, edge geometry, stain resistance vs wear resistance and toughness and RC hardness enough times in my life already, I am firmly of the opinion that MAYBE most people are not capable of knowing what it is that they have in their hand.
But… I am have also seen more than enough people use a well designed knife, well sharpened and steel chosen for the work I intend to do with it to also have the opinion that almost all of them know that when I hand them one of my knives they are not using what they are used to.
They almost invariably notice and comment something on the order of “holy crap that thing is sharp!”. Frequently they are the same people who use a saw or loppers of some sort to separate the ribs from the sternum on deer or when removing the feet from the shanks, use an axe or loppers. When they get to watch someone with the right knife and the skill to use it they ask “holy crap! how did you do that so fast?” Those are the people who do not know the difference because they have no idea of the tools they use for most things. Those people may well make up 80%-90% of the population, and only maybe 10% of them are bright enough to ask questions to find out what you know that they don’t!
They go to a grocery store and buy a ridiculously high Vanadium content kitchen knife and use it until it goes dull and then either toss it or take it to a commercial knife sharpener who uses power tools. Some few of them will try to sharpen one of those knives with a silicon carbide stone they do not begin to know how to use.
What they do not know about knives is not something they will probably EVER recognize as a deficiency on their part.
Some issues to be taken into account include:
* Confounding variables: You mention geometry, but there are others. Sharpening technique/abrasives, blade weight and thickness, edge length and shape (straight vs curved), even the design of the handle affecting cutting technique, all can influence results.
* Interaction effects: when one input to a system changes the influence of another input. For example, if one steel forms a toothier edge than another using the same sharpening method, then you are not comparing the performance of the steels but that of a toothier edge vs a less toothy one. Therefore, you must design your sharpening method to eliminate interaction with steel type, which is not a trivial problem. Geometry can also interact with steel type, which means that controlling for edge angle and thickness is not enough.
* Unblinding: For example, if one steel rusts but another doesn’t, the user knows which is which, and may handle them differently in ways that affect measures other than corrosion.
* Sampling error: There can be tremendous random variation from one trial to the next, so you have to determine how much testing is needed to accurately estimate effect sizes.
* Confirmation bias: When results are expected, they are accepted readily, but when they aren’t, people make up theories and explanations even though similar explanations could apply to expected results.
* Validity: Even if tests are perfectly controlled, data carefully analyzed and the effect of steel rigorously quantified, how well does it apply to the average Joe using the tool in daily work? Can that be changed by educating or influencing users?
* Cost/benefit: When discussing fuel economy, the benefit is obvious and easy to quantify: you are saving fuel cost. But if Joe Blow gets to sharpen his knife x% less often, how much does that improve his productivity? How much does it add to the value of the tool?
If the differences among steels were large enough (say 100 to 1), a lot of these issues could be ignored, but because they aren’t that big, any assessment of real-world performance has to be very carefully planned, analyzed and applied. So while a 5-to-1 difference might seem like a vast gulf, it doesn’t justify dismissing the nuances of experimental study design.
Phrasing this as “you can’t tell the difference” may be crude and inflammatory, but fundamentally, I think the point is the same.
A woodworker (and sometimes toolmaker) view. I can, as many of us, obviously tell a difference in the knives. The idea that someone would pick up magnacut and not notice the difference vs 1075 or something is pretty far out there, but I guess it begs the question of use. If someone isn’t using their knife or the knife is dull no matter what steel they use, maybe they can’t tell.
Larrin’s mention of hardness is true. In the woodworking community, people often claim V11 (CTS-XHP) and A11 (10V) are the same, or call steel A1 and O2, or both with the same number. There’s an inability for most to differentiate what they observe due to hardness vs. alloy. A company made 10V irons for us to use in planes, but at high 50s hardness. I new they were trouble immediately based on how they sharpened. As larrin said about 26c3 at lower hardnesses – you lose the point if you don’t use the steel for what it’s good at (10V in this case just isn’t good for “cold” woodworking with hand tools).
Almost nobody is using woodworking tools with crucible steel, which is great for the task, but anyone who is more than 1 month into the hobby can tell that in an easy task where edge stability isn’t an issue, a higher alloyed steel lasts longer at a task and takes longer to sharpen than cast crucible. We sharpen all the time if we are actually working on something, as the entire hobby is impact damage or abrasive wear.
Whether or not it provides the average user any utility if they learn to sharpen in a minute is an entirely different subject.
what is not debatable is the manufacturers that make boutique tools for us cannot handle the skill needed to harden water hardening steel, and the world of A2 and Magnacut and XHP makes for greater ease for manufacturers who need design for amateurs who have little ability to prepare a new tool (it needs to arrive ready or very close).
So for a chopper (leaving edge geometry out for now) how would you estimate which steel would fare better? I imagine the CATRA edge retention would be of lower importance than hardness and toughness but it probably still matters especially when the steels are similar hardness, right? Would be interested in something which can approximate this use case.
I would think wear resistance wouldn’t matter much for purely chopping
So as long as the steel is tough enough not to chip (which probably isn’t something you could put a concrete number to) the harder steel probably would do better no matter what type?
The highest combination of toughness and hardness would do the best. But at which hardness that would happen would be hard to guess without experimenting with the specific edge geometry and use case.