In the 1950s and 1960s, Josef Kupper was one of the leading Swiss chess players.

In 1959, Josef Kupper participated in the Zürich International Chess Tournament, which took the 9th place, the highest among all Swiss chess players playing in the tournament.

[2] Josef Kupper played for Switzerland in the Chess Olympiads:[3] Josef Kupper played for Switzerland in the European Team Chess Championship preliminaries:[4] Also Josef Kupper twelve times participated in Clare Benedict Chess Cup (1953, 1956, 1958, 1960, 1962–1963, 1966–1967, 1969–1970, 1972–1973) and in team competition won gold (1958), silver (1969) and two bronze (1953, 1960) medals, and in individual competition won five gold (1953, 1956, 1963, 1969, 1970) medals.

[5] In 1955, he awarded the FIDE International Master (IM) title.

This biographical article relating to a Swiss chess figure is a stub.