Mardenborough had not seriously raced prior to entering GT Academy.
Mardenborough's rise is unusual because up until 2011 at the age of 19 he had never seriously competed in motorsport.

In 2011 Mardenborough participated in the GT Academy; he beat 90,000 other entrants and won the competition, and the prize for his victory was a drive with Nissan at the Dubai 24 Hour.
He scored third in his class.
In 2012 Mardenborough competed in the British GT Championship.
Together with Alex Buncombe he won a race and ended the season in sixth place in the GT3 championship.
Moreover, he took part in four rounds of the Blancpain Endurance Series.

In 2013 Mardenborough switched to formula racing.
At the beginning of the year Mardenborough started in the 2013 season of the Toyota Racing Series in New Zealand.
He was the best placed rookie and finished the season in the tenth place in the championship.
After that he returned to Europe and secured a seat with Carlin Motorsport in the 2013 campaign of the FIA European Formula Three Championship, as well as the British Formula 3 Championship.
After one season in F3 Mardenborough joined Arden International to compete in the 2014 GP3 Series season, and was also signed by the Red Bull Junior Team driver development programme.
He won his first GP3 race in Germany after a reverse grid pole position in the sprint race and setting the fastest lap.

At the 2014 Goodwood Festival of Speed, Mardenborough set the fastest ever Supercar time up the famous "Goodwood Hill" whilst piloting the Nismo Nissan GT-R with the optional ‘Time Attack’ package.

Mardenborough also continued racing in GP3, switching to Carlin for the 2015 season.

On 28 March 2015, his GT3-class Nissan GT-R Nismo caught air at the Flugplatz section of the Nürburgring Nordschleife.
It cartwheeled over the fence into spectators.
One person was killed, while Mardenborough was not seriously injured.

Mardenborough's achievements and growing global profile led to Sports Pro Media naming him on their list of the 50 most marketable athletes in the world.

From 2017, Mardenborough raced in the Super Formula Series in Japan with Toyota.
From 2017 to 2018, Mardenborough competed for Team Impul in Super GT.
In 2019, he raced for Kondō Racing.
Mardenborough had not seriously raced prior to entering GT Academy. Mardenborough's rise is unusual because up until 2011 at the age of 19 he had never seriously competed in motorsport.
In 2011 Mardenborough participated in the GT Academy; he beat 90,000 other entrants and won the competition, and the prize for his victory was a drive with Nissan at the Dubai 24 Hour. He scored third in his class. In 2012 Mardenborough competed in the British GT Championship. Together with Alex Buncombe he won a race and ended the season in sixth place in the GT3 championship. Moreover, he took part in four rounds of the Blancpain Endurance Series.
In 2013 Mardenborough switched to formula racing. At the beginning of the year Mardenborough started in the 2013 season of the Toyota Racing Series in New Zealand. He was the best placed rookie and finished the season in the tenth place in the championship. After that he returned to Europe and secured a seat with Carlin Motorsport in the 2013 campaign of the FIA European Formula Three Championship, as well as the British Formula 3 Championship. After one season in F3 Mardenborough joined Arden International to compete in the 2014 GP3 Series season, and was also signed by the Red Bull Junior Team driver development programme. He won his first GP3 race in Germany after a reverse grid pole position in the sprint race and setting the fastest lap.
At the 2014 Goodwood Festival of Speed, Mardenborough set the fastest ever Supercar time up the famous "Goodwood Hill" whilst piloting the Nismo Nissan GT-R with the optional ‘Time Attack’ package.
Mardenborough also continued racing in GP3, switching to Carlin for the 2015 season.
On 28 March 2015, his GT3-class Nissan GT-R Nismo caught air at the Flugplatz section of the Nürburgring Nordschleife. It cartwheeled over the fence into spectators. One person was killed, while Mardenborough was not seriously injured.
Mardenborough's achievements and growing global profile led to Sports Pro Media naming him on their list of the 50 most marketable athletes in the world.
From 2017, Mardenborough raced in the Super Formula Series in Japan with Toyota. From 2017 to 2018, Mardenborough competed for Team Impul in Super GT. In 2019, he raced for Kondō Racing.
Jann Mardenborough