Jan van Dort started playing football at VV Heemstede at age 13 and subsequently for EDO (Haarlem). In 1910 he moved to Amsterdam and made his début for Ajax as a midfielder but for some years could not get a regular spot on the first team. Once he started playing regularly he also started scoring a lot of goals, 73 in total, as he and Jan de Natris were responsible for three quarters of Ajax’ goals. For three seasons Van Dort was the club’s top scorer including the 1920 season, when he was selected for the Olympic team. In 1922, Van Dort moved to Arnhem to work there, where he continued his career at Vitesse and also managed the club until 1924. He earned five caps, all of them in 1920. Van Dort worked as a typesetter, and later owned a factory. His older brother Henk also played one senior match for Ajax.