1. Lewis Hamilton
Series: Formula One
Team: Mercedes-AMG Petronas
Salary and earnings (2017): $38 million
One thing to know: Taking endorsements into account, Lewis Hamilton is the highest-paid driver in the world and the richest athlete in all of the United Kingdom. His favorite things to spend money on include classic cars, private jets and an art collection.
Source: Forbes
2. Sebastian Vettel
Series: Formula One
Team: Scuderia Ferrari
Salary and earnings (2017): $38 million
One thing to know: Vettel won four consecutive Formula One championships between 2010 and 2013, cementing his status as the greatest German driver since Michael Schumacher.
Source: Forbes
3. Fernando Alonso
Series: Formula One
Team: McLaren-Honda
Salary and earnings (2017): $34 million
One thing to know: A two-time Formula One champion, Alonso is the only Spanish driver to win an F1 Grand Prix in the series' history. He made his first career appearance at the Indianapolis 500 earlier this year.
Source: Forbes
4. Jimmy Johnson
Series: NASCAR Cup Series
Team: Hendrick Motorsports
Salary and earnings (2017): $16.8 million
One thing to know: With five consecutive championships between 2006 and 2010, as well as two more in 2013 and 2016, Johnson is one of the greatest drivers in the history of racing.
Source: Forbes
5. Kyle Busch
Series: NASCAR Cup Series
Team: Joe Gibbs Racing
Salary and earnings (2016): $13.5 million
One thing to know: Busch has been a prolific winner since he debuted as a 19-year-old rookie in 2005. Among active drivers, only Jimmie Johnson can top his total of 40 career victories.
Source: Forbes
6. Denny Hamlin
Series: NASCAR Cup Series
Team: Joe Gibbs Racing
Salary and earnings (2016): $13.4 million
One thing to know: With three podium finishes and more than 30 race wins, Hamlin is one of the top NASCAR drivers to never win a championship. At fifth in points, that could change this year.
Source: Forbes
7. Dale Earnhardt Jr.
Series: NASCAR Cup Series
Team: Hendrick Motorsports
Salary and earnings (2017): $13.4 million
One thing to know: The son of a seven-time Cup Series winner, Dale Earnhardt Jr. is one of the faces of NASCAR. He's been named NASCAR's Most Popular Driver for 14 years in a row and counting, but that reign will end soon enough – he's retiring at the end of this season.
Source: Forbes
8. Kevin Harvick
Series: NASCAR Cup Series
Team: Stewart-Haas Racing
Salary and earnings (2016): $10.9 million
One thing to know: A former Cup Series champion, Harvick isn't afraid to speak his mind. Earlier this year, he blamed Dale Earnhardt Jr.'s massive popularity for NASCAR's failure to connect with a wider fan base.
Source: Forbes
9. Matt Kenseth
Series: NASCAR Cup Series
Team: Joe Gibbs Racing
Salary and earnings (2016): $10.2 million
One thing to know: With the 2003 championship and 38 career Cup wins to his name, including two at the Daytona 500, Kenseth is one of the most accomplished NASCAR drivers active today.
Source: Forbes
10. Kasey Kahne
Series: NASCAR Cup Series
Team: Hendrick Motorsports
Salary and earnings (2016): $9.8 million
One thing to know: Kahne picked up the biggest victory of his career earlier this year at the Brickyard 400. The win snapped a drought of nearly three years.
Source: Forbes
11. Joey Logano
Series: NASCAR Cup Series
Team: Team Penske
Salary and earnings (2016): $9.7 million
One thing to know: Logano won his first race when he was just 19 years old, edging veterans Jeff Gordon and Kurt Busch at New Hampshire in 2009.
Source: Forbes
12. Brad Keselowski
Series: NASCAR Cup Series
Team: Team Penske
Salary and earnings (2016): $9.6 million
One thing to know: Keselowski enjoyed a rapid rise to the elite ranks of NASCAR, winning the 2012 Cup Series in just his third full season.
Source: Forbes
13. Valtteri Bottas
Series: Formula One
Team: Mercedes-AMG Petronas
Salary and earnings (2017): $8.5 million
One thing to know: With wins in Russia and Austria, Bottas has been a consistent force in his first year with Mercedes. He'll be a free agent at the end of the season.
Source: Fox Sports
14. Danica Patrick
Series: NASCAR Cup Series
Team: Stewart-Haas Racing
Salary and earnings (2016): $7.2 million
One thing to know: Patrick is one of the highest-paid NASCAR drivers in the sport, but she doesn't perform like it. Through nearly five full seasons, she has yet to post a top-5 finish in any race.
Source: Forbes
15. Kimi Raikkonen
Series: Formula One
Team: Scuderia Ferrari
Salary and earnings (2017): $7 million
One thing to know: Ten years removed from his lone Formula One championship, Raikkonen isn't having his best season, but he did notch a strong second-place finish at the Hungaroring in July.
Source: Fox Sports