Tanjiro is a young boy of average height with fairly tanned skin and an athletic, muscular physique. He has ruffled, black hair with burgundy tips, combed back to expose his forehead, and wide, dark red eyes with white pupils that appear lighter around the lower section of his irises. He also has a scar on the top left of his forehead, first seen when his mother brought him to watch his father perform the Hinokami Kagura dance. The scar originally looked somewhat like a graze until his fight with the Hand Demon during the Final Selection, after which it develops into a flame-like pattern as his Demon Slayer Mark. It is noted that his hands are visibly rougher for someone his age, as a result of his rigorous training under Sakonji Urokodaki. Tanjiro looks remarkably similar in appearance to his ancestor Sumiyoshi, possessing the same facial structure, eyes, and hairstyle as him, although Sumiyoshi’s hair was longer, about shoulder-length and would be tied in a ponytail behind his head.
Tanjiro first appears wearing a checkered, black-and-sea-foam-green haori over a white robe and black pants. He occasionally sports a turquoise scarf and is seen with circular, white bands looped around his calves. He also wears a distinct pair of hanafuda earrings, with the image of the rising sun over a mountain. His hair is also kept tied back in small ponytail or bun; as he trains with Sabito and Makomo, his hair grows to his shoulders.
During the Final Selection, Tanjiro wears a blue, cloud-patterned samue-styled kimono and black pants, nearly identical to Sakonji’s outfit. He still wears his hanafuda earrings, but his hair is cut extremely short and remains the same length since. Similar to the rest of the apprentices that were trained under Sakonji, Tanjiro wears a hand-carved fox mask crafted from his master on the left side of his head. The mask has red accents on the eyes, ears, and spots on each corner of its mouth. On the upper right corner of the mask, there is a sun-shaped design that likely symbolizes the scar on his forehead.
After becoming a Demon Slayer, Tanjiro wears the standard Demon Slayer uniform, a dark-brown gakuran jacket, a white belt, baggy chocho zubon pants that extend into tabi socks, a pair of zōri with red straps, and bands of white cloth wrapped tightly around his calves resembling kyahan, all beneath his signature checkered haori. He carries a large wooden box on his back (which was a gift to him from Sakonji Urokodaki), where his sister sleeps as they travel during the day.
During his second encounter with Muzan Kibutsuji, he injures his right eye in the Infinity Castle. As the battle progresses, Tanjiro suddenly collapses and his wound begins to form a large mass over his right eye due to the poison inflicted on him by Muzan. Later on, when Tanjiro wakes up, he is described as looking ‘repulsive’ by Muzan. Later in the battle Tanjiro’s left arm is severed by Muzan.
After being turned into a demon by Muzan, Tanjiro is able to heal the growth on his face as well as regenerate his lost arm and other smaller injuries. He obtains eyes with slit pupils, fangs and flame-shaped marks over his left forehead and right jaw that are reminiscent of those of Kokushibo, in addition to a third, smaller flame-shaped mark coming down from the right side of his head down to his eyebrow after he conquered the weakness to sunlight. His scar turns into a flame-pattern as if it were a permanent Demon Slayer Mark, has become longer and is the largest of the three, and all three marks vaguely point towards his nose, though only his scar-mark reaches it. He still dons his bloodstained corps uniform, one sleeve ripped off where his arm was severed, but loses his checkered haori and the Nichirin Sword at his hip.
After returning to his human form, Tanjiro loses the ability to see from his right eye, the iris of which is now a dull pink-gray color and the pupil black rather than its original white. His left arm, which he regrew as a Demon, now takes the appearance of that which an older person may have, becoming wrinkled and skeletal, and he loses all feeling in it below the elbow and thus the ability to move it from his forearm down.
Personality
Tanjiro is kind by nature and has been described by others as having very gentle eyes. He exhibits a great deal of determination and will not give up once he has a goal to achieve; the best example of this is his relentless quest to find a cure for Nezuko.
Even though he is relatively strong on his own, Tanjiro isn’t opposed to asking others for help when he needs it. He is very protective of his friends and even more so of his younger sister. However, despite his kind and understanding nature, Tanjiro does have a limit to his tolerance and has a distaste for rudeness, as he easily becomes annoyed by Zenitsu Agatsuma’s constant whining, and angered by Inosuke Hashibira’s barbaric actions.
Tanjiro’s most notable attribute is his ability to empathize with anyone, even demons, which often made him hesitate before delivering the final blow. This moment of hesitation has a downside, as it has allowed some Demons to take advantage of Tanjiro’s understanding nature to recover and continue the fight, though this occurs rarely.
However, as Tanjiro gained experience over the years of his service, he becomes more calculating and strict in his decisions. His courage to protect the weak commits him to face his enemy with respect and dignity, whether versus good people or evil Demons.
Powers and Abilities
Hard Skull: Tanjiro has a hard skull he inherited from his mother. His head is very durable to the point in a single headbutt, it’s physically strong enough to cause immediate damage to his opponents. One example is where he manages to stun Sanemi, the Wind Hashira.
Sense of Smell: Tanjiro possesses a sense of smell bordering on superhuman territory. Even before becoming a Demon Slayer, Tanjiro was known in a village as the boy who has an extremely strong sense of smell equivalent to that of hounds, bears and sharks etc.. He is able to pick up even the most subtle of scents and track their location with terrifying accuracy over long distances. It is strong enough for him to smell the ‘opening thread’, the slight pause in an enemy’s movement which allows him an opening in which to strike.
Enhanced Strength: After his training at Mount Sagiri, Tanjiro has gained superhuman arm and leg strength and has demonstrated a great use of it, jumping over the humongous Hand Demon, and leaping over buildings effortlessly. Tanjiro also casually broke Genya’s arm and shattered Inosuke’s ribs and sent him flying all with a single punch. With his katana, he could slice through gigantic boulders and entire trees. While training, Tanjiro is capable of doing hundreds of push-ups at once along with a plethora of other strength-related exercises. When he was posing as a courtesan, he was shown to carry dozens of large boxes easily and when he was angered, he ripped off an Upper Rank’s leg. When he was training with Gyomei Himejima, he was tasked with lifting 3 enormous logs on his back and pushing a boulder through town. He later managed to cut off Akaza’s head, a feat which even Kyojruo couldn’t accomplish.
Immense Stamina & Endurance: Tanjiro has incredible stamina and endurance, even before he became a Demon Slayer, showed when he had to train in a mountain will little to no oxygen for many days, dodging booby traps, running and traversing through it up and down, and improving his swordsmanship skills and physique all while under these harsh conditions. His stamina and endurance was further improved having mastered Total Concentration: Constant allowing him to exert himself physically 24/7. He was able to rejoin the fight against Daki and Gyutaro despite him nearly crossing his life limit just minutes prior. His stamina was increased even further after he mastered the Hinokami Kagura, the same Breathing Style which allowed his sickly father to dance till dawn in the snow while barely clothed.
Combined Breathstyles: Tanjiro combines Water Breathing and Hinokami Kagura together. This allowed a fatigued Tanjiro to move quickly to save Hinatsuru from Gyutaro. He would later use these combined breathing styles again during the Infinity Castle Arc to slay dozens of demons.
Recovery Breathing: A technique developed by Tanjiro that allows him to recover from fatigue and stiff muscles that prevent his body from moving, which he uses to overcome the whiplash of using Hinokami Kagura techniques twice in a row.