[3][4] He achieved his greatest success winning the 24 Hours of Le Mans in 2016 after first joining Porsche's LMP1 programme for the 2014 season driving in the FIA World Endurance Championship.

[5] Previously, Jani drove for A1 Team Switzerland in A1 Grand Prix, helping them win the 2007–2008 title and finishing runner-up in 2005–06 and 2008–09.

He joined Formula E's Faraday Future Dragon Racing squad for the 2017/2018 season but left the team after one weekend.

Born in Rorschach, Switzerland, to an Indian father from Gujarat and a Swiss mother, Jani started his career in karting in 1998, where he stayed for two years before moving up to Formula Renault 2000 Eurocup in 2001.

In the inaugural season of A1GP, the team earned the silver medal for second place, with Jani consistently finishing on the podium, including a win at the Dubai Autodrome of the 2005-06 United Arab Emirates Sprint race.

In June 2023, it was announced that Jani had signed with Audi as a simulator driver to help them develop their power unit in preparation for their entry into Formula 1 in 2026.

[10] On 24 August 2017, it was announced that Jani would make his debut in FIA Formula E Championship in its fourth season at Faraday Future Dragon Racing with Jérôme d'Ambrosio as his teammate.

[11] After two 18th-place finishes at the season opener in Hong Kong, Jani abruptly quit the team focusing instead on his WEC commitments with Rebellion Racing.

[12] In December 2018, Porsche announced that Jani would return to the championship as part of their driver line-up for their maiden season.

[13] He raced for Porsche with teammate Andre Lotterer till the end of the 2019–20 season, finishing twentieth on the standings.