Johan Frithiof Isidor "John" Svanberg (1 May 1881 – 11 September 1957) was a Swedish runner.
He competed in the 5 miles and marathon at the 1906 Intercalated Games and 1908 Summer Olympics and won two silver and one bronze medals.
In 1908 he set a world record over 3000 m that stood until 1911.
After the 1908 Olympics Svanberg was deprived of his amateur status for some commercial activities.
He moved to the United States, where he worked as a painter and continued competing in running.