Forfang began ski jumping in his hometown at the age of twelve before moving to Trondheim at the age of 16 due to the better training conditions. In the 1997/1998 season, Forfang made his debut at the Continental Cup . However, it was not until December 21, 2001 that he was used for the first time in a World Cup competition in Predazzo, Italy , where he reached a 39th place. His first World Cup points took the Norwegians in January 2002 with a 14th place at the competition in the Japanese Hakuba .
In the 2002/2003 season Forfang was mainly used in the Continental Cup, which he finished with a fifth place overall. He celebrated two wins in a row in Zakopane , Poland this season . In the following season Forfang was used again in the Continental Cup, which he finished in 18th place. It is noteworthy that he suffered a ligament injury in his ankle while playing volleyball in the summer, which he did not have treated until after the end of the season. However, he already returned to the competition for the Summer Grand Prix , although he had previously expressed thoughts of resignation. In the competitions he was able to celebrate a victory with the team in Zakopane and two individual victories in Innsbruck and Hakuba.
Because of these results, he returned to the World Cup team in winter 2004/05 and achieved his best place in the overall World Cup with rank 28. This season he was able to achieve his only victory with the team, this was the case on March 5, 2005 in Lahti . His personal best in ski flying also dates from this season, he set it up in the qualification for the competition in Planica, Slovenia on March 18, 2005 when he flew 214 meters. In the 2005/2006 season , Forfang was only partially used in the World Cup.
On August 28, 2006 Daniel Forfang ended his career as an active athlete due to problems with the Norwegian Ski Federation and the pressure to slim. It is interesting that the coach claimed that Forfang's competition weight was 70 kilograms, but he himself stated in an interview after finishing his career that he had a competition weight of 61.7 kilograms.
Daniel Forfang is currently assistant trainer at Team Trønderhopp in Trondheim , where he is involved in looking after the elite group and, together with his former jumper colleague Morten Solem , the first junior group.