Tai is a happy-go-lucky and adventurous person. He is very caring and considerate of others, even if his actions may cause some people to think otherwise. He tends to act impulsively and rush without realizing the consequences of his actions, especially when his friends are in danger. However, he is quick to realize and admit he has been wrong, and does whatever it takes to fix his mistakes. It takes time for him to learn how to be a leader, but eventually he grows into the unifying force that leads all the other DigiDestined. As a teenager, he has learned to to look further ahead and not to act brashly, though he is still an easygoing sort. He becomes a calm and mellow mentor to the new DigiDestined.
Tai's younger sister, Kari, is one of the eight DigiDestined, and the last one to join the team. Tai is very close to Kari and very protective of her, in part because of their past experiences. On her part, Kari idolizes Tai and confides in him even when they are older. Tai and Kari used to share a room, but sometime between Digimon Adventure and Digimon Adventure 02 Kari has moved to another room.
Tai's oldest friend is Sora Takenouchi, who has been in the same class as him since the first grade. In elementary school, they are both regulars in the soccer club. His closest friend is Koushiro "Izzy" Izumi, who he met at the soccer club. As the adventurous leader of the group, Tai is always the first to jump into action, though it often throws him into the path of danger. His ideas often conflict to Matt's, resulting in a fight.
(In Digimon Adventure tri) Tai's usual focus on the "big picture" leads him to become more cautious about battling after seeing the destruction caused by the Digimon's battles, and his resolve falters against the risk of collateral damage. When it becomes clear that Digimon like Alphamon will only cause more damage if they aren't stopped, Tai makes the decision to fight against them, but he still remains uneager to battle.