Takushi Izawa

Izawa was born on May 16, 1994, in Ōmiya City (now part of Ōmiya-ku, Saitama City), Saitama Prefecture. He later moved to Ibaraki Prefecture and was an only child in a dual-income household. His father is Takashi Izawa, a former office worker at Yomeishu Seizo Manufacturing Company. His father introduced him to reading.

He attended Gyosei Elementary School. He said during this time he was interested in football and wanted to be a professional football player but he said that he lacks the skills to do it. He researched various topics including World Cup participants. He said this was the first time he discovered the "fun in gathering knowledge". He attended the Kaisei Middle School after his friends said that they were taking the entrance exam for that middle school. This was where he first joined a quiz club, which had eight members. He graduated from Kaisei High School in Tokyo, at which he became the first person to win the solo division of the All Japan High School Quiz Championship two consecutive times, doing so in 2010 and 2011. He enrolled in the University of Tokyo's Faculty of Economics, where he became part of the university's Quiz Club. He tried to enroll for a Master's degree in economics but was rejected, and instead went to the Faculty of Agriculture.

Izawa was in a three-month relationship when he was 20.

In an interview with the medical blog “Medical Doc”, Izawa said that he used to suffer from severe myopia, and from the second grade of elementary school, he wore glasses, and from college, he said that could not let go of contact lenses. He later received an ICL surgery.