Kevin Jan Magnussen was born on 5 October 1992 in Roskilde, Denmark, as the son of former Formula 1 driver Jan Magnussen and Britt Petersen.
In 2005, Magnussen started his karting career. After the year 2005, he won the Peugeot Super Kart ICA Junior Championship and the NEZ Championship in the ICA Junior class in 2006.
In 2008 he made his debut in cars. In his debut year he immediately won a race, set the fastest lap and achieved the pole position for a race in the NEZ Formula Ford Championship. In 2008 he drove six races for Frits van Amersfoort in the ADAC Formel Masters Championship, achieving two podiums. The most important championship for Magnussen that year was the Formula Ford championship in Denmark.
He became champion with eleven victories in fifteen races. In 2009 he came second in the Formula Renault 2.0 NEC championship and in 2010 he switched to the ATS Formula 3 championship in Germany. After a third place in the 2011 British Formula 3 Championship, he became a test driver at McLaren. Magnussen drove in the Formula Renault 3.5 series for two seasons and became champion in 2013.
At the end of 2013, an opportunity arose to replace Sergio Perez at McLaren in 2014. In his very first race in Formula 1, Magnussen drove to the podium. It turned out to be the only real highlight of the season. After a year on the bench, he signed for Renault in 2016.
After another difficult year, he made the switch to the Haas F1 team in 2017. In 2018 he finished ninth in the championship with the American team.