He composes most of Seventeen a songs, that's why he's called "the genius composer".
He was a former member of ‘Tempest’ before Seventeen was created.
His favorite food is Jjajangmyun (Black Bean Noodles) & Spicy Ramyun Noodles mix together.
He likes sports.
He love rice.
He was voted by the other members as the most hard working member, along with Soonyoung.
He says he feels burdened being Seventeen’s composer because he’s afraid if they fail, it would be his fault.
He answered once in a fansign that he "won't do anything" when he has someone he likes. (Basically, he would not confess or make a move to someone he has a crush on.)
He views himself as being very calm, serious and careful. Because he’s a little too serious sometimes, he has the nickname ‘documentary’.
The meaning behind his real name is that Ji means ‘know’, Hoon means ‘service’. It means to know my service.
When he was younger, he did classic music for a long time. He played the clarinet and band instruments. He always enjoyed singing and people told him he had a good voice but he was doubtful. He participated in the Pledis auditions and passed. Since then, his knowledge on music has widened and it becomes more exciting to him each time.
Between winter or summer, he prefers winter.
Bumzu mentioned once that Woozi has this one expression when he is done making a song that he really likes. He will say "I just sent the song through email~ give it a listen~" and he will come to Bumzu's studio room while crossing his arms (very cutely) with a smile.
He participated in making fromis_9's LOVE RUMPUMPUM as one of the composer, lyricist and arranger. He used a pseudonym '백구' (BaekGu) meaning White Jindo dog.