2021 Formula One World Championship

The 2021 Formula One World Championship was the 72nd season of the Formula One World Championship. The motor racing championship is the highest class of competition for open-wheel racing cars.
Entries
The following constructors and drivers were under contract to compete in the 2021 World Championship. All teams competed with tyres supplied by Pirelli. Each team was required to enter at least two drivers, one for each of the two mandatory cars.
Free practice drivers
Across the season, five drivers drove as a test or third driver in free practice sessions. Callum Ilott and Robert Kubica drove for Alfa Romeo Racing at two and three Grands Prix respectively, while Roy Nissany and Jack Aitken drove for Williams at three Grands Prix and at the Abu Dhabi Grand Prix, respectively. Zhou Guanyu drove for Alpine at the Austrian Grand Prix.
Team changes
McLaren announced that they would change from using Renault power units to ones built by Mercedes, resuming the McLaren-Mercedes partnership that ran between and . Racing Point became known as Aston Martin. The name change was brought about by the team's part owner Lawrence Stroll investing in the Aston Martin marque. Renault became known as Alpine, taking on the name of Renault's sportscar brand.
Driver changes
Four-time World Drivers' Champion Sebastian Vettel left Ferrari at the end of the Championship after racing with the team for six seasons. Vettel's seat was taken by Carlos Sainz Jr., who had left McLaren. Daniel Ricciardo moved from Renault to McLaren, where he replaced Sainz. Ricciardo was replaced by double World Champion Fernando Alonso, who drove in Alpine's first season, having last raced in for McLaren.
Vettel moved to Aston Martin, where he replaced Sergio Perez. Perez, who had previously signed a contract to drive for Aston Martin's predecessor, Racing Point, until 2022, moved to Red Bull Racing where he replaced Alex Albon, who was Red Bull Racing's reserve and test driver for the 2021 season. Perez became the first driver since Mark Webber in to join the team without being previously a Red Bull Junior Team member.
Romain Grosjean and Kevin Magnussen, who had raced for Haas since and respectively, left the team at the end of 2020. 2020 Formula 2 Champion Mick Schumacher, the son of seven-time World Champion Michael Schumacher, took one of the seats at the team while the other was filled by Nikita Mazepin, who finished fifth in the Formula 2 Championship.
Yuki Tsunoda, who finished third in 2020 Formula 2 Championship, graduated to Formula One with Scuderia AlphaTauri, replacing Daniil Kvyat, who moved to Alpine as their reserve driver. Tsunoda became the first Japanese Formula One driver since Kamui Kobayashi in .
Mid-season changes
During the Dutch Grand Prix weekend, Kimi Raikkonen tested positive for coronavirus. He was replaced at Alfa Romeo Racing by reserve driver Robert Kubica, who last raced at the 2019 Abu Dhabi Grand Prix, driving for Williams. Raikkonen was also replaced by Kubica at the subsequent Italian Grand Prix.
Nikita Mazepin did not take part in the Abu Dhabi Grand Prix due to positive of coronavirus tests. Haas only fielded one car at the event, rather than replacing Mazepin by reserve driver Kevin Magnussen.