- Name: Inoo Kei (伊野尾慧)
- Nickname: Inoo-chan, Inoo Kei-chan, Kei-kun, Kei, Kei-chan
- Birthdate: June 22, 1990
- Horoscope: Cancer
- Birthplace: Iruma, Saitama Prefecture, Japan
- Blood Type: A
- Height: 174cm
- Weight: 58kg
- Shoe size: 26.5cm
- Eyesight: 0.8(Right) 0.8(Left)
- Schools: Touyou Koto (High-school), Meiji University (Architect Department)
- Subject that good in: History
- Admired Senior: Kimura Takuya, KAT-TUN
- Respected Senior: Sakurai Sho
- Date entering Johnny's: 23rd September 2001
- Charming Point: Hand (Beautiful like girl's hand)
- Favorite Food: Rice, Salty-Mackerel
- Dislike Food: Spinach
- Favorite Fruit: Strawberries
- Valuable Thing: Letters from Fan Club
- Favorite Type of Girl: Cute, Kind, Smart and Responsible
- Talent: Basketball, Drawing, Guitar, Piano
- Family: Parents and 2 Younger sisters (Aki & Keiri)
- Pets: Miniature Schnauzer called "Jam" & "An" (Twins, Female)
On September 23, 2001, he entered Johnny & Associates as a trainee, along with Kota Yabu, whom later becomes one of his best friends. On September 24, 2007, he began performing as a member of Hey! Say! JUMP.
- His favorite color is sky blue, and he hates the color green and yellow.
- His hobby is learning English. He likes to study new English words.
- The type of girl that he likes is a girl who has manners and has common sense.
- Doesn't like Mathematics and English, despite the fact that he keeps studying English. He hopes someday he would learn to love this subject.
- He likes studying different things.
- He has a younger sister, Aki Inoo, who he said has a bad attitude and mouth.
- He can play the piano. He is seen playing the piano for performances of Star Time.
- Is often seen wearing caps in paparazzi pictures.
- He passed his high school exams and got into the Department of Architecture, School of Science and Technology at Meiji University.
- He is said to always telling random lie by Yuya Takaki.
- He has this love-hate thing of riding a roller costers.
For Hey! Say! JUMP-related appearances, please see Hey! Say! JUMP.
- The Shōnen Club
- 100shiki (百識王)
- Hayaguchi no Boogie (solo at Tengoku Concert)