Stoffel Vandoorne was born in Kortrijk. Vandoorne was introduced to motorsport at the age of six during a visit to the kart track of World Karts in Kortrijk in Flanders, Belgium. Vandoorne started karting after the owner of the track gave him a mini-kart.
Initially, lack of funding restricted Vandoorne to race 3 to 4 races per year. By age 16 he was Belgian KF2 Champion. In 2009 he finished as runner-up in the CIK-FIA World Cup in the KF2 category. The same year he won the 'steering wheel' competition held by the Royal Automobile Club of Belgium. The prize money of 45,000 euros helped him start his car racing career in F4 Eurocup 1.6.
In 2010, Vandoorne moved up to single-seater racing, joining the F4 Eurocup 1.6 series. He went on to win the series on his first attempt, finishing the season with six wins and three further podium finishes. The prize from winning the series helped him to move up to the Eurocup Formula Renault 2.0 the following year. He also earned a place in the FIA Driver Academy.
In 2011, he graduated to competing in the Eurocup Formula Renault 2.0 with Kurt Mollekens' KTR team. He finished fifth overall, with one podium at the Hungaroring and another eight-point-scoring finishes throughout the season. He also participated in , where he finished third in the series' standings with eight podiums.
For the 2012 season Vandoorne remained in the Eurocup, but left KTR to join JoseFormula Renault 2.0 Northern European Cupf Kaufmann Racing. He won the championship by ten points after a tight battle between himself and Red Bull-backed Daniil Kvyat. Between them they won 11 of the 14 races and finished over 100 points ahead of their nearest challenger. Vandoorne finished the season with four wins and six podiums to his name. He also contested selected events in the Northern European Cup, where he won five of the seven races that he started, and finished on the podium in a sixth race.
In 2013, Vandoorne raced in Formula Renault 3.5, where he replaced 2012 champion Robin Frijns at Fortec Motorsport. He finished runner-up to fellow McLaren young driver Kevin Magnussen with four wins and 10 podiums, including a victory at his home track of Spa-Francorchamps.
In January 2014, it was confirmed that Vandoorne would make his debut in GP2, racing with ART. In the opening race at Bahrain, Vandoorne claimed his first victory of the season in the feature race. He followed this up with four consecutive pole positions, three more wins at the Hungaroring, Monza and Yas Marina and six additional podiums. Despite being a rookie, he finished runner-up to 2014 champion Jolyon Palmer.
Vandoorne reunited with ART for 2015, as well as was considered the main title contender. He was partnered by 2014 Japanese Formula Three champion Nobuharu Matsushita. After five feature race wins, twelve podiums and four pole positions, Vandoorne took the title in Sochi, 108 points over his nearest rival Alexander Rossi.
On 12 February 2016, it was announced that Vandoorne would race a Honda in Super Formula for Dandelion Racing. He finished fourth overall, the highest ranking among Honda engine users, with two wins and one pole position at Fuji Speedway in wet conditions throughout the season.
In February 2013, Vandoorne joined McLaren's Young Driver Programme, under the tutelage of his then manager Richard Goddard, in collaboration with the team's sporting director Sam Michael and its head of communications Matt Bishop, to whom Vandoorne had been introduced in 2011 by Alex Wurz.
In January 2014, he was announced as a third driver for McLaren F1 also taking up driving duties in the GP2 Series for ART Grand Prix.
On 31 March 2016, it was announced Vandoorne would be replacing regular driver Fernando Alonso at the Bahrain Grand Prix after the Spaniard was ruled unfit to drive following a major accident in the previous round. After qualifying 12th ahead of Jenson Button, Vandoorne finished 10th and became the first reserve driver to score points on debut since Sebastian Vettel at the 2007 United States Grand Prix.
On 3 September 2016, ahead of the Italian Grand Prix, it was announced by McLaren that Jenson Button would not be racing in 2017, and that Vandoorne would be replacing him to partner Alonso for the 2017 season.
In his debut full season at McLaren, Vandoorne established himself as a considerable rookie next to veteran F1 Champion, Fernando Alonso. With the uncompetitive McLaren, Vandoorne racked up 13 points compared to Alonso's 17. The key issues lied in the reliability and performance of the car which resulted in 1 DNS and 5 DNFs throughout the 20 race season. Nevertheless, he managed to crack into the top 10 in Hungary, Malaysia and Singapore.
On 23 August 2017, it was announced that Vandoorne would be retained for the 2018 season.
In the new McLaren Renault partnership, Vandoorne enjoyed a good start to the season with 3 points finishes in the first 4 races. However, as the season progressed, he struggled to maintain this momentum which has left him with 8 points by the Japanese Grand Prix. Moreover, the lack of a competitive package in the McLaren has resulted in a long drought in points finishes between the 2018 Azerbaijan Grand Prix and the 2018 Mexican Grand Prix. Vandoorne ended the season in 16th ahead of 4 other drivers in the drivers' championship. However, the last few Grands Prix saw Vandoorne in some impressive battles particularly in the Abu Dhabi Grand Prix in his battle with Ocon and Grosjean which lead him to finish 8th on the Formula 1 Power Rankings.
It was announced on 3 September 2018 that Vandoorne would leave McLaren at the end of the 2018 season.
Vandoorne will be the simulator driver for the Mercedes team in 2019.
It was confirmed on 15 October 2018 that Vandoorne would drive for HWA Racelab for the 2018–19 Formula E season. He would be joining Britain's Gary Paffett to complete the driver lineup for HWA Racelab.