Karl Fredrik Valdemar Thorin was born on May 30, 1904 in Göteborg and made his IFK Göteborg debut in the 1926/27 season, which was also the debut season of team mate Herbert Samuelsson. Thorin was part of IFK Göteborg's youth program before making his debute with the first team, and is as a result of that regarded by the club as a home-grown player. At 22 years, 11 months and 12 days, on May 13, 1927, he took part his first competetive game against Örgryte IS in an Allsvenskan game that ended 2–1. He spent one season with the IFK Göteborgs first team, and during his career he played in 8 first team games. Out of these 8 first team games, 4 were Allsvenskan games.
Karl Thorin is with his 4 Allsvenskan games number
400 on the list of those who have competed in most Allsvenskan games for IFK Göteborg. Thorin passed away in 1990, 86 years old.