Why Is Tanjiro’s Sword Black In Demon Slayer? Theories Explored

Koyoharu Gotouge’s Demon Slayer is known for its fascinating world, cool designs, and Nichirin Swords! Since Nichirin swords and their colors were revealed, fans were eager to learn more about them!

Out of all the swords, Tanjiro’s sword has remained a major point of discussion due to its unique, black color!

In this article, we’re going to take a look at all the theories as to why Tanjiro’s sword is black in Demon Slayer. 

However, let’s take a quick look at Nichirn Swords first!

Colors of Nichirin Swords Explained:

It is generally considered that the color of a demon slayer’s sword is associated with their Breathing technique.

However, the user must have a certain level of skill for the blade’s color to change.

For example, Flower Breathing users Kanae Tsuyuri and Kanao Kocho have light pink blades. Flame Breathing users tend to have blades with a bright red color.

These colors can have unique patterns too, like Zenitsu’s sword, which has a yellow zig-zag pattern, symbolizing his lightning technique.

Talking about unique blades, Haganezuka expected Tanjiro’s blade to be bright red. This was because of the protagonist’s bright eyes and red hair, which are signs of fortune.

But, fate wouldn’t agree, and handed a black sword to Tanjiro.

So, Why Did Tanjiro’s, Sword Turn Black?

It is considered that demon slayers with black blades die early due to a lack of skill.

Apart from this, the Demon Slayer Corps have no information on the color either!

Throughout the series’ length, we didn’t get to know much about the blade. However, fans have created some theories by putting two and two together.

Let’s dive into the most plausible ones:

The Black Blade Signifies Tanjiro:

One theory suggests that Tanjiro’s blade is black because his name symbolizes his connection with charcoal and fire.

The kanji for “tan” means charcoal, and the first half of his surname “kama” is a Japanese furnace that is used with charcoal.

Furthermore, the Kamado Family’s business was selling charcoal too!

Black Is The Color Of Sun Breathing:

To understand the connection between Black Blades and Sun Breathing, we have to take a look at Rengoku’s knowledge of the blade, as it proves to be vital here.

He explained how breathing styles were created and their connection to the nichirin blades.

He could explain the five basic breathing styles, but couldn’t explain the Sun breathing as nobody had heard of Hinokami Kagura before.

This means that the color of a Sun Breathing user’s blade is unknown!

Regnoku then explains more about the black blade users, which leads us to our next clue.

Firstly, no black blade user has ever been a Hashira, tying into the assumption that demon slayers with this sword don’t live for long.

Secondly, Rengoku adds that he has heard that black blade users can’t find a specific breathing style to master.

This also ties to Tanjiro’s case, who was originally a Water Breathing user and discovered Sun Breathing later.

As we know, Tanjiro would go on to use both styles of breathing, further supporting what Rengoku had learned!

Now, Tanjiro is an important piece in the world of Demon Slayer, and so are the things he carries with him.

For example, his family heirlooms, the Hanafuda Earrings, and the Hinokami Kagura dance hold major significance as well.

Tanjiro’s ancestors were close friends of Yoriichi Tsugukuni, the progenitor of breathing styles.

He also created Sun Breathing.

While other breathing styles became popular, Sun Breathing was overshadowed as it was far more complex. Due to this, only a handful of people could learn Sun breathing.

As Demon Slayers increased in numbers, most abandoned the hope of learning Sun breathing.

This led to the creation of “five basic styles of breathing” to teach aspiring demon slayers.

Another reason for the “extinction” of Sun Breathing is Muzan. Yoriichi was the only man who ever came close to defeating him.

This became a traumatic event for the king of demons, who sought to kill anybody who possessed Yoriichi’s potential.

Muzan was successful in killing all Sun breathing users as soon as they learned it.

This led to the loss of all information about the breathing style. The loss of info was then worsened by Kyojuro’s father Shinjuro, who vandalized the records regarding the breathing styles.

Furthermore, Muzan’s actions explain why demon slayers with black blades died early. They didn’t lack skill, in fact, their potential was far greater than others.

While the color of Yoriichi’s blade hasn’t been made official, the design and no mentions of his blade’s colors have led many fans to assume that he wielded a black nichirin blade too!

Furthermore, fans also believe that since Sun breathing was the first breathing style, the user’s blade would be black.

This is because black can absorb all colors, symbolizing how Sun breathing gave birth to the other breathing styles!

Science Makes The Blades Black:

The third theory behind the color of Tanjiro’s blade is more practical than the others, quite literally.

Nichirin blades are said to have the ability to absorb sunlight, which kills demons.

Black is the best absorber of sunlight, which would let black blades absorb the highest amount of sunlight on average, making them stronger than your average-colored blade.

However, a demon slayer would need a breathing style that could keep up with the blade’s powers!

These are some of the most popular theories behind Tanjiro’s blade’s color!