Jakub Fibigr was born in Unicov, Czechoslovakia.
In 2021-2022. Fibigr played for Vitkovice U-17 and in 36 games played he tallied 10 goals and 18 assists. In 2022-2023, he played for Vitkovice Jr. team and scored two goals and 12 assists in 43 games.
Fibigr was selected by Mississauga of the OHL in 2023. His first year in the OHL, Fibigr played in 61 games and recorded seven goals and 36 assists. He was selected to play for Team Czechia in the WU18 and scored one goal in five games.