Coulthard was born on 27 March 1971 in Twynholm, Kirkcudbrightshire, Scotland, one of three children to road haulier Duncan Coulthard and Elizabeth Joyce Coulthard née Marshall. His family was connected to motor racing: his grandfather competed in the Monte Carlo Rally and his father drove karts, becoming Scottish National Champion. From an early age motorsport was where his interest lay, later listing Formula One World Champions Jim Clark, Nigel Mansell and Alain Prost as his childhood heroes. Coulthard was educated at Kirkcudbright Academy, achieving eight O Level certificates.

Coulthard began karting when his father presented him with his first kart for his eleventh birthday. Having won several local karting championships including the Scottish Junior Kart Championship and the Scottish Kart Championship, Coulthard participated in events further down the UK, including title victory in the Cumbria Kart Racing Club Championship in 1985. Coulthard graded each race he entered on a scale of 1 to 10, with an additional column headlined “Performance”. He later gave credit to David Leslie, senior and junior for allowing his career to develop.

In 1989, Coulthard made the transition from karting to car racing. It is often erroneously claimed that he won the British Formula Ford Championship that season, however this is not the case. Coulthard actually won the lesser P&O Ferries Formula Ford 1600 Junior championship.

He became the first recipient of the McLaren/Autosport Young Driver of the Year award, which allowed him to test a McLaren Formula One car. In 1990, Coulthard travelled to Belgium to compete in the EFDA Nations Cup for Great Britain and was partnered with Nicky Hart, where they finished 9th. During the year, Coulthard was selected by Vauxhall Motorsport to race in a one-off appearance in the British Touring Car Championship (BTCC) at Brands Hatch, where he finished 13th. He did not return to the series after suffering a leg injury in a Formula Vauxhall race at Spa-Francorchamps.

For 1991, Coulthard signed with Paul Stewart Racing to compete in the British Formula 3 series, taking five victories and finishing second in the Championship behind Rubens Barrichello. Coulthard won the Macau Grand Prix and the Masters of Formula Three. He later traveled to the Fuji Speedway to compete in the annual Formula Three Fuji Cup, taking pole position and finished second behind Jordi Gené.

In 1992, he moved to the International Formula 3000 series, where he suffered from a lack of competitiveness and finished ninth in the championship. For 1993, Coulthard joined Pacific Racing, taking one victory and finishing third in the series. He entered the 24 Hours of Le Mans alongside John Nielsen and David Brabham for the TWR Jaguar Racing team. The trio won the GT Class, although they were later disqualified for a technical infringement. He moved to the Vortex team in 1994, which received investment from a private investor, allowing Coulthard to drive for the team. In his first and only race for the team held at Silverstone, Coulthard finished third.

Throughout 1993 and 1994, Coulthard was employed by Williams Grand Prix Engineering team as their official test driver. A race seat became available after the death of Ayrton Senna in the 1994 San Marino Grand Prix. Coulthard received a telephone call from team principal Frank Williams to test the Williams car at Jerez circuit over four days, causing him to miss a Formula 3000 race at Pau.

In 1995, Coulthard again competed with Williams alongside Damon Hill. He was optimistic for the season, saying: “I’d like to think I can win a Grand Prix this year. That’s really my aim, plus to score points in as many races as possible.” Coulthard’s season started off with controversy when he and Benetton driver Michael Schumacher were disqualified for fuel irregularities in the first round in Brazil, where Coulthard finished second. On appeal, the original results of both drivers were reinstated. The next five races saw four retirements for Coulthard, plus a fourth-place finish in San Marino.

For 1996, Coulthard partnered experienced driver Mika Häkkinen at McLaren, and believed there was a chance of winning races, though a challenge for the World Championship was unlikely until 1997 or 1998. His season started badly; he suffered a throttle issue in Australia, including a collision with Jordan driver Martin Brundle on the first lap. Coulthard spun off in Brazil and finished outside the points in Argentina. However, Coulthard secured a podium at the Nürburgring and led the race in San Marino before suffering a hydraulic failure.

In 1997, Coulthard again partnered Häkkinen at McLaren. He started his season by taking victory in the opening round in Australia. Coulthard was unable to score in the next four rounds, due to being involved in a collision in Argentina and contended with unreliability with his car. The factor of unreliability had an impact throughout the season, which became notable in Canada when Coulthard made a pit stop while leading and the car developed clutch problems. He suffered from four more retirements throughout the season, and was able to take victory at the Italian Grand Prix.

In 1998, Coulthard remained at McLaren and continued to be partnered by Häkkinen. The season started controversially in Australia for the McLaren team when Coulthard, who was leading let Häkkinen past to win the race. Coulthard later revealed a pre-race agreement by the team that whoever led into the first corner on the first lap would be allowed to win the race. However, the race marked a run of consistent results, with Coulthard scoring three further podiums, including victory in San Marino. Coulthard retired from three out of the next four races, and followed this up by taking a further five podiums during the remainder of the season, including a retirement in Italy.

For 2000, Coulthard reorganised his schedule for the season, concentrating on his performances and spending less time working on promotional campaigns. Many motorsport critics labelled 2000 as Coulthard’s “make or break” year.

On 2 May 2000, while he was leasing the Learjet of friend David Murray, the aeroplane developed engine trouble en route to Côte d’Azur International Airport in Nice and crashed while attempting an emergency landing at Lyon-Satolas Airport, France. Coulthard, his then-girlfriend the American model Heidi Wichlinski and personal trainer/bodyguard Andy Matthews survived; Murray’s personal pilot David Saunders and co-pilot Dan Worley died. Coulthard and Wichlinski ended their relationship before the beginning of the 2001 season, which was followed with a series of inaccurate newspaper reports about alleged affairs with other women.

The 2002 season was the first in which Coulthard was the more experienced driver in his team. He was optimistic for the new season, saying: “If they need an opinion then they have to come to me this year. In the past they didn’t. But that said, it’s important for me not to get bogged down in the history of what happened in the past. We just have to go forward.” He endured a torrid start: Coulthard’s car suffered from gearbox issues and retired after 35 laps; and in the following race in Malaysia, both cars retired from engine failure after 24 laps. Two weeks later in the Brazilian Grand Prix, Coulthard secured his first podium of the season with a third-place finish. The start managed to get better as Coulthard took four consecutive finishes inside of the points; this included his only victory of the season in Monaco.

Following the purchase of the Jaguar team by Red Bull, Coulthard announced on 17 December 2004 that he would leave McLaren to move to Red Bull for the 2005 season. He signed a one-year deal for a reported £1.8 million to drive alongside Austrian driver Christian Klien. Coulthard was offered a testing role at Ferrari, which he declined as he decided to remain in a race seat.

On 4 December 2004, Coulthard participated in his first Race of Champions for Great Britain alongside 1995 World Rally Champion Colin McRae. Coulthard was eliminated in the quarter-finals of the racing group having taken a time penalty, losing to Heikki Kovalainen. Coulthard and McRae were again chosen to compete in 2005, when the event was held in Stade de France. Coulthard was eliminated in the Round of 16 by Tom Kristensen and Great Britain were defeated by France in the semi-finals of the Nations Cup. In 2006, Coulthard was eliminated in the quarter-finals stage by Yvan Muller.

Coulthard was involved in a four-year relationship with Brazilian model Simone Abdelnour, before ending the relationship in 2005. Coulthard became engaged to Karen Minier, a Belgian Formula One correspondent for French TV channel TF1, on 2 June 2006. The couple planned to marry “in the near future”. Coulthard and Minier had their first child, Dayton Minier Coulthard, on 20 November 2008.

Coulthard stayed with Red Bull in 2006, and continued to be partnered by Klien. Coulthard started his season with retirements in Bahrain and in the following race in Malaysia whilst running tenth. The next three races saw Coulthard finish outside the points-scoring positions with consecutive retirements in San Marino and the Nürburgring. Coulthard secured Red Bull Racing’s first podium position by finishing 3rd in Monaco. He managed to finish in the next ten races he entered which included finishing in the points in Canada, the United States and Hungary.

Coulthard’s helmet design is blue and consists of a white saltire on the top which resembles the flag of Scotland and the four tips are trepassed from the top of the chin area. Coulthard borrowed a helmet belonging to Michael Schumacher for the 1996 Monaco Grand Prix as his regular helmet was suffering from steaming up during the weekend. Upon Schumacher’s first retirement in 2006, he suggested to Coulthard that he would swap one of his own helmets for one of Coulthard’s, which was agreed by Coulthard. For the 2007 Japanese Grand Prix, he changed his design to grey with a stylised saltire on the sides of his helmet, as an homage to the late World Rally Champion Colin McRae.

Coulthard continued as a driver at Red Bull in 2007, partnered by Webber. He endured a torrid start: Coulthard retired in Australia following a collision with Williams driver Alexander Wurz, and in the following race in Malaysia, he retired with brake problems. In Bahrain, Coulthard ran in eighth position before his car developed driveshaft problems and was forced to retire. He was able to score his first points of the season by taking fifth position in Spain.

For 2007, Alister McRae partnered Coulthard after Colin McRae was killed in a helicopter crash. For the second consecutive year, Coulthard was eliminated at the quarter-final stage, this time by Sébastien Bourdais. On 30 October 2008, Coulthard was announced as one of the competitors of the event in 2008 for F1 Racing Great Britain, held at Wembley Stadium on 14 December. He reached the final of the Drivers’ Cup and lost out to World Rally Champion Sébastien Loeb. In 2009, Coulthard raced for the All-Stars team alongside Giniel de Villiers. The pair were eliminated in Group B of the Nations Cup, and Coulthard was defeated in the quarter-finals of the World Finals by Sebastian Vettel.

Coulthard finished outside the points, with consecutive retirements in Canada and the United States, before he secured fifth position in the European Grand Prix. In July, it was announced that Coulthard would remain with Red Bull in 2008. Coulthard secured tenth position in the Drivers’ Championship, with 14 points, and helped Red Bull secure fifth place in the Constructors’ Championship.

On 25 November 2008, it was announced that Coulthard would join the BBC as a pundit alongside Jake Humphrey and Eddie Jordan for the broadcaster’s coverage of Formula One. With the departure of commentator Jonathan Legard at the end of 2010, Coulthard was announced as a co-commentator alongside Brundle, after undergoing successful screen tests. He also writes a regular column for The Daily Telegraph and BBC Sport.

Coulthard did not participate in 2010 and was replaced by BTCC driver Jason Plato. Coulthard returned for 2011, joining the All-Stars team alongside Filipe Albuquerque. The All-Stars pairing were eliminated in the group stages, with Coulthard eliminated in the quarter-finals of the Drivers’ Cup by Martin Tomczyk. In 2012, Coulthard remained in the Race of Champions and returned to compete for Great Britain, partnering Andy Priaulx. The pairing were eliminated in the group stages, with Coulthard being eliminated during the semi-finals by Kristensen in the Drivers’ Cup.

On 4 April 2010, Coulthard announced a return to motor racing when he secured a contract to drive for Mücke Motorsport and would be partnered by Maro Engel. Coulthard started the season by finishing in the first two races and retired from a collision in Lausitz. He managed to secure a further five consecutive finishes, although he did not score points in these races. Coulthard retired on the first lap of the next race at the Hockenheimring when he was involved in a multi-car collision. Coulthard rounded out the season with an eighth-place finish in Shanghai. Coulthard finished 16th in the Drivers’ Championship, with one point, and Mücke finished eighth in the Teams’ Championship.

Coulthard was appointed Member of the Order of the British Empire (MBE) in the 2010 Birthday Honours for services to motorsport.

On 6 April 2011, it was announced that Coulthard would be retained by Mücke and would once again be partnered by Engel. Coulthard stated at 2010 was his “apprenticeship year” and pledged during 2011, that he would become more competitive. Coulthard started off his season by finishing in the first four races, albeit outside the points-scoring positions. He secured his only points of the year at the fifth race of the season at the Norisring, where he finished 8th. The remainder of the season saw Coulthard finish every race, although he was disqualified from the race at Ricardo Tormo as his car’s rear wing was found to have been incorrectly mounted during the qualifying session. For the second consecutive year, Coulthard finished 16th in the Drivers’ Championship, with one point, and Mücke secured eighth in the Teams’ Championship.

On 29 February 2012, it was announced that Coulthard would once again be retained by Mücke and would be partnered by Robert Wickens. Coulthard finished in the points with 8th position in the opening round held at the Hockenheimring. He did not score points in the next three races, which included a retirement at the Red Bull Ring. He recovered from this to take fifth position in the next round at the Norisring. Before the final race at the Hockenheim, Coulthard announced his retirement from motor racing, citing the reason to spend more time with his family and to concentrate on his co-commentary role with the BBC, as well as managing his off-track businesses. Overall, Coulthard secured fifteenth in the Drivers’ Championship, with 14 points, and Mücke clinched tenth in the Teams’ Championship.

For 2013, Coulthard was to be partnered by Williams development driver Susie Wolff, the first female competitor in the history of the Race of Champions. However, two weeks before the event was due to take place in Bangkok, the Sports Authority of Thailand and Race of Champions organisers announced the event would be cancelled due to political unrest in Thailand. For 2014, Coulthard went onto the Nation’s Cup with Wolff and the pair reached the final, finishing runner-up to Team Nordic’s Tom Kristensen and Petter Solberg. Coulthard then went on to win the Driver’s Cup after beating Pascal Wehrlein in the final to claim his first Race of Champions Driver’s title.

A museum in his home village, Twynholm, was dedicated to Coulthard, but it has now closed. It was previously run by Coulthard’s sister, who died in February 2013. Fans in his home village are called “Twynosi” (a cross between Twynholm and the Italian word for “fans”, tifosi, as used by Ferrari fans), who gather on race days. He released his autobiography in 2007, entitled It is What It Is. In it, he stated that he had suffered from bulimia as a teenager, caused by the need to lose weight when competing in karting championships. In 2008, Coulthard was best man at the wedding of Christian Hughes and actress/presenter Amanda Holden.

In 2016, Coulthard left the BBC to join Channel 4 after the BBC abandoned its coverage of Formula One. With Channel 4 he continued to commentate and be a co-presenter of their Formula 1 coverage. Coulthard co-owns Whisper Films, along with former co-presenter Jake Humphrey, and the production company was chosen by Channel 4 to produce its coverage of all of its races. He was offered a presenting role on Top Gear alongside Jordan but turned down the offer because “Channel 4 pulled a blinder”. Coulthard also presented Channel 4’s highlights of the 2017 Race of Champions.

For the 2017 Mexico City ePrix he made a guest appearance as an analyst for Channel 5 coverage.

On 10 October 2018, Coulthard was announced as a spokesperson and advisory board member of the forthcoming W Series, a racing championship for women based on Formula 3-homologated Tatuus T-318 chassis.