He won a silver medal in the 6 metre class with the boat Elisabeth X at the 1952 Summer Olympics in Helsinki,[1] together with Finn Ferner (his brother), Erik Heiberg, Tor Arneberg and Carl Mortensen.

[1] Johan Ferner was the son of master tailor Ferner Jacobsen (1884–1964), who established a department store in Oslo, and his wife, Ragnhild Olsen (1889–1966).

[1] His grandfather was maritime pilot Johan Martin Jacobsen (1850–1907) from Tjøme, son of blacksmith Jacob Andreas Knudsen (1819–1868).

Firstly, on 20 January 1953, Johan Ferner married artist Ingeborg 'Bitte' Hesselberg-Meyer (later Rostad; 1931–1997).

He then remarried at Asker Church outside Oslo on 12 January 1961 to Princess Astrid of Norway, the second daughter of King Olav V of Norway and Princess Märtha of Sweden.