Tanjiro is kind by nature and has been described by others as having very gentle eyes. He has a great deal of determination and will not give up once he has a goal to achieve; an example is finding a cure for Nezuko. Even though he is relatively strong on his own, he 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. His most important attribute is his ability to empathize with anyone, even demons. This often makes him hesitate when killing demons. However, this trait also could make some Demons to redeem themselves moments before death, albeit rarely.

For the years of his service and amount of experience he faced, he became more calculating and strict in his decision. His courage to protect the weak committed him to face his enemy with respect and dignity whether good or evil demons.