Davidson is currently racing for Toyota Hybrid Racing in the FIA World Endurance Championship. He raced in Formula One for Minardi and Super Aguri, and was a test or reserve driver for the British American Racing, Honda, and Brawn GP teams.
Born in Hemel Hempstead, he is nicknamed 'Ant' due to his diminutive size.
Like most racing drivers, Davidson started racing in karts in 1987, racing in various British, European and North American championships. In 1999 he moved to cars, racing Formula Fords and winning the McLaren/Autosport Young Driver of the Year Award in 2000. In 2001 he competed in the European and British Formula Three championships, winning the former and coming runner-up in the latter. In this year he became the test driver for BAR, whilst in 2002 he started two races for Minardi, retiring from them both.
In 2004 BAR were able to run a third car in Friday morning testing, and Davidson was given the honor. He frequently impressed with his pace, although some have questioned the validity of these times as a raw indicator due to the lack of need to conserve the car in the way the race drivers Button and Sato did. Contrary to popular rumor, only 2 of his fast times were set on light fuel - a fact his father has repeated many times on internet forums.
In November 2004, BAR announced that it had failed to come to an acceptable contractual agreement with Williams to allow Davidson to drive for the latter team in 2005 (because Williams would not agree to his unconditional "repatriation" to BAR in 2006). Given BAR's long-term contract on Davidson, his chance of securing a race seat for 2005 was therefore called into serious doubt. He was given the opportunity to fill in for an ailing Takuma Sato at the 2005 Malaysian Grand Prix, but his Honda engine expired into flames just two laps into the event.
In 2006 Davidson resumed his role as test driver for BAR, now owned by Honda and renamed Honda Racing F1. As BAR had failed to be one of the top four constructors the previous season Honda were able to run a third car on Friday, giving Davidson a bigger role than in 2005. Having previously done some radio commentary work for BBC Radio Five Live, in 2006 he made his debut as a television commentator, standing in for the absent Martin Brundle for ITV Sport at the Hungarian Grand Prix, which was won by Jenson Button and the Honda team. In 2008 Davidson returned to Honda as test driver for the testing at Spain's Circuit de Catalunya whilst Honda test driver Alexander Wurz was racing at Le Mans.
On 15 November 2006, Super Aguri confirmed that Davidson would partner Takuma Sato for the 2007 Formula One season. Thus, he became a regular Formula One driver for the first time.
At the 2007 Canadian Grand Prix Davidson was running third when his car struck a groundhog on the straight before the pits, ultimately putting him back to 11th place and ending his bid for his first career points. At the Hungarian Grand Prix Davidson's rear suspension was broken during a collision with Giancarlo Fisichella, which forced him to retire. Davidson finished the season in 23rd place having scored no points. Davidson driving for Super Aguri at the 2008 Malaysian Grand Prix.
Amid financial problems which threatened their continued participation in Formula One, Super Aguri retained Davidson alongside teammate Sato for 2008. However, on 6 May 2008 Super Aguri withdrew from the Championship leaving Davidson without a race seat.
Davidson was announced as a Honda test driver for the remainder of 2008. On 5 December 2008 Honda pulled out of Formula One due to financial problems. Ross Brawn bought out the team and formed Brawn GP and Davidson signed on as a test driver. On 16 November 2009, engine suppliers Mercedes-Benz bought out Brawn GP and renamed the team Mercedes GP. Davidson continued in his role and reserve and development driver.
Davidson was linked with incoming teams Virgin and Lotus for the 2010 F1 season. However, Davidson did not secure a 2010 race seat in F1, and instead turned his focus to racing sports cars. In F1 he continued his long-standing relationship with the Brackley-based Mercedes F1 Team, combining duties as reserve and simulator driver in 2010 and 2011, and continuing his simulator role into 2012 and 2013.
Davidson raced for the Aston Martin Racing team in the 2009 24 Hours of Le Mans, alongside Darren Turner and Jos Verstappen. His team drove Lola-Aston Martin B09/60 in the LMP1 class, which finished 13th overall in the race. He returned in the 2010 edition, driving for defending champions Team Peugeot Total alongside Alexander Wurz and Marc Gené. The trio warmed up for Le Mans by leading a Peugeot 1–2 in the 2010 12 Hours of Sebring. However, in the Le Mans race his Peugeot car had an engine failure while leading. Following Le Mans, Davidson raced at the 2010 6 Hours of Silverstone with Nicolas Minassian and secured victory for Peugeot Sport. In October 2010, Davidson secured pole position at Petit Le Mans, and went on to finish second with teammates Alex Wurz and Marc Gené.
In 2011, racing the 908 for Peugeot Sport, Davidson along with Wurz and Gené, won the 6 Hours of Spa, and finished 4th at the Le Mans 24 Hours. Teaming up with Sébastien Bourdais, Davidson went on to win the 6 Hours of Imola, and the 6 Hours of Zhuhai, victories which helped Peugeot Sport secure the Intercontinental Le Mans Cup (ILMC) Championship for the second year running. Davidson at the 2014 24 Hours of Le Mans
With Peugeot pulling out of factory sports car competition, Davidson signed with Toyota to drive its Toyota TS030 Hybrid in the 2012 24 Hours of Le Mans. Five hours into the race, as Davidson was lapping the AF Corse Ferrari 458 Italia GTC of Piergiuseppe Perazzini, the two cars collided at the end of the Mulsanne Straight. The collision turned Davidson's car sideways before becoming airborne, flipping through the air, before landing back on its wheels and made heavy contact with the barriers. Davidson initially tried to get out of his car before calling for assistance; he was later transferred to hospital where he was later diagnosed with fractures to the eleventh and twelfth thoracic vertebrae of his back.
In 2013, Davidson continued driving with Toyota for a full season and ended with third place in the drivers' championship. For the 2014 season, he drove Toyota's new car Toyota TS040 Hybrid, winning 4 races, and became 2014 World Endurance Drivers' Champion with Sébastien Buemi.
He has since been heard as a co-commentator on selected Grands Prix for BBC Radio 5 Live. This became permanent on 13 February 2009, when it was announced he would commentate alongside David Croft for the 2009 season. Davidson has continued in the role through 2010 into 2011, as the BBC decided on an unchanged lineup for its radio Formula One coverage. On 7 December 2011, Sky Sports announced that Davidson would join its British team as an analyst for race weekends, and would be commentating on practice sessions from the 2012 season.