What can a katana cut through?

by Niklas Feurstein
Katana (CC BY 2.0) by Emmanuel H.

You probably already heard people claiming that katanas can cut even tanks in half. They go even this far and say that katanas are superior to every other melee weapon.

In this article, we will find out what materials a katana can cut through.

Can a katana cut through anything?

First, let’s begin with a broader question.

Japanese katanas are really sharp weapons. This is mostly due to the high carbon content of the steel.

I always compare the steel of historical katanas to the regular 1095 high carbon steel used nowadays.

The steel used for forging the samurai blades is able to take and keep a really sharp edge. However, the high carbon content makes the sword a little bit brittle.

Therefore, the durability of the sword suffers from impacts.

Exactly this point leads us to an interesting clue to our question. No real samurai wants a blunt or bent sword.

For this reason, they tend not to parry or block with their sword (at least not with the sharp edge). As a conclusion, we can say that a katana can definitely NOT cut through anything.

In contrast to European swords, they were way more fragile.

Now you might ask what they can slice through?

Exactly this question we will answer now.

Can a katana cut through plate armour?

Plate Armour
Plate Armour by Kunsthistorisches Museum [CC BY 3.0]

I hear severe misconceptions on this question all the time.

First of all, no real swordsman wants their blade to bump against steel armour.

So let’s come right to the answer.

Neither a European sword nor a katana can cut through plate armour.

Even though katanas are very sharp they just aren’t made for this purpose.

In a one-on-one fight, both fighters will try to find gaps in the opponent’s armor.

Plate armor is thick and extremely hard, therefore no sword stands a chance at cutting through it.

Why can’t a katana cut through plate armour?

Yeah, as stated before most swords weren’t able to accomplish this.

Reason being that they were designed for a different purpose. The katana, for example, was a cutting weapon. It was developed against fighting lightly armored targets.

However, even knights and samurai were equipped with weapons to hurt enemies wearing a full plate suit.

There are lots of European and Japanese polearms that can cause severe trauma to plate armor wearers. Yet they are far from penetrating it.

Swords were a weapon of last resort after all. Against armored targets they perform particularly poorly.

Attacking your enemies from distance is a much safer bet.

Therefore a reasonable weapon order was (depending on the century): matchlock > bow > spear > sword.

But let’s get back to the katana.

When striking with a sword the force is evenly distributed along the entire part of the blade that has contact with the target. So your attack energy is reduced.

As the sword and armor are made from the same material it is obvious that there can’t be any medieval weapon that is able to pierce plate armor (except the arquebus).

What impact does a katana strike have on an armoured target?

As we now know that a katana can’t pierce through plate armour, what impact does the strike have?

I commonly see this question in a lot of forums. People are debating if the target would feel any pain at all.

The armoured knight faction always claims that if there is no cut in the armour the target would not feel any pain.

This argument is oftentimes supported because the knights wore a gambeson jacket under the plate armour as well.

These statements always make me laugh. It’s really funny :D Of course, a slash from a sword will hurt you!

However, the impact of a strike wouldn’t be enough to toss you on the ground. Though, if you were surprised by the attack it may well be possible.

Most guys seem to misunderstand the purpose of armour.

It’s not there to keep you from getting hurt. It’s in place to keep you from getting killed!

In this regards armour does its job extremely well.

The only point, where a direct sword hit is very likely to get you killed, is the head. An attack with full force will probably lead to a concussion.

As a result, you will certainly lose the battle.

Can a katana cut through chain mail?

Chain Mail

As we just talked about plate armour let’s move on to another armour type.

Can a katana really cut through chain mail? That’s a common question I get asked a lot.

Ironically most people think that chain mail is inferior to plate armour. However, the protection against katanas and other swords is similar to plate armour.

You won’t get killed. Therefore the chain mail does its job.

Yeah, in terms of shock resistance chainmail combined with gambeson is weaker than steel armor.

However, this is an unfair comparison. Chain mail was widely used during the middle ages.

Only the nobility could afford the exorbitant costs of full plate armour. Even professional infantry was mainly equipped with chain mail.

Therefore, it makes sense that plate armour is a bit better.

Back to the question if a katana can cut through chain mail.

The short answer is: NO!

However, with proper edge alignment and a lot of luck, a sword could cut out a few rings of the chain mail (but only if the smith didn’t put much effort into making it).

This process would need to be repeated multiple times, which is very unlikely to happen in real combat. In this scenario, we have to factor in that the samurai sword gets blunt after a few tries.

Therefore, we can conclude that it is impossible to cut through mail armor with a katana.

If you want to know whether other medieval weapons can cut through armor check out my plate vs chainmail complete guide.

Can katanas cut through bones?

Now, this is the part where it gets interesting.

So a sword can’t cut through plate armour nor chain mail.

What do you think can it cut through? Maybe human bones?

Let’s assume the same testing conditions as before. A really sharp katana, which is swung with full force.-

The answer is quite obvious for all the people who always claim that a katana can cut through anything.

Luckily for them, a katana can cut off the arm (or head) of an opponent.

There are three main factors that directly influence whether or not a sword can cut through bones. One of those factors depends on the blade wielder.

First of all the weight of the blade increases its cutting abilities. More mass means more force to smash some bones.

In contrast to European great swords the katana is really light.

Second is the sharpness of the blade. As katanas are forged from very high carbon steel they can certainly take and keep a very sharp edge.

The third factor depends mainly on the wielder of the blade. It’s the force at which the weapon is swung.

However, a blade heavy weapon (which the katana is) is more likely to build up more force.

The stronger the person wielding the blade the greater the damage.

These factors also apply to the armour parts we covered. Although they make no difference there (armoured opponent still survives).

Why is a katana so sharp?


The answer to the bone question led me to another totally different question.

Why is a katana so sharp? Does it really need to cut off an entire arm?

Finding a solution to this was rather complicated. I tried doing some research, but I couldn’t find a clear answer.

In my opinion, there is no real reason why a katana is so sharp.

Being able to cut off limbs is not a real advantage. European swords that cut from the flesh to the bone, would also render an entire arm completely useless.

The only difference being that with a katana strike the opponent would bleed to death more quickly.

Maybe you are more experienced in this topic than I am. If you got more helpful information feel free to share it in the comment box below.


We have now reached the end of this post.

Therefore, I want to quickly summarise the main points.

A katana is NOT able to cut through plate nor mail armour.

Soldiers were equipped with other weapons to deal with armored targets. But even polearms can’t pierce plate. The goal is to cause internal damage like bone fractures to incapacitate your enemy.

However, a katana is able to chop off entire limbs.

I hope that I could help you solve some common misconceptions about katanas.

See you in the next post! Stay tuned.

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