IndyCar Series
Highest winning percentage
25 or more starts are needed to appear on the list for F1, Champ Car, IndyCar, MotoGP, NASCAR Xfinity, or NASCAR Trucks, while 50 or more starts are needed for Cup.
| Driver | Winning percentage |
| Will Power | 18.4000 |
| Scott Dixon | 17.2093 |
| Sam Hornish, Jr. | 16.3793 |
| Gil de Ferran | 16.1290 |
| Arie Luyendyk | 14.2857 |
| Dario Franchitti | 13.9073 |
| Dan Wheldon | 12.0301 |
| Tony Stewart | 11.5385 |
| Juan Pablo Montoya | 11.4286 |
| Hélio Castroneves | 9.9138 |
| Ryan Hunter-Reay | 9.8592 |
| Kenny Bräck | 8.6957 |
| Buddy Lazier | 7.8431 |
| Scott Goodyear | 7.6923 |
| Tony Kanaan | 7.3733 |
| Greg Ray | 6.8493 |
| Eddie Cheever | 6.4935 |
| Scott Sharp | 6.1224 |
| Simon Pagenaud | 5.6338 |
| Mike Conway | 5.5556 |
| James Hinchcliffe | 5.4795 |
| Al Unser, Jr. | 5.3571 |
| Ryan Briscoe | 5.1852 |
| Sébastien Bourdais | 4.0541 |
| Richie Hearn | 4.0000 |
| Sam Schmidt | 3.7037 |
| Bryan Herta | 3.4483 |
| Alex Barron | 3.2258 |
| Buddy Rice | 3.0303 |
| Josef Newgarden | 2.9851 |
| Carlos Muñoz | 2.7027 |
| Robbie Buhl | 2.5641 |
| Airton Daré | 2.5641 |
| Justin Wilson | 2.5000 |
| Graham Rahal | 2.3077 |
| Eliseo Salazar | 1.8868 |
| Buzz Calkins | 1.8868 |
| Ed Carpenter | 1.8868 |
| Jaques Lazier | 1.7857 |
| Mark Dismore | 1.7241 |
| Tomas Scheckter | 1.6949 |
| Jeff Ward | 1.6393 |
| Felipe Giaffone | 1.6393 |
| Billy Boat | 1.5873 |
| Marco Andretti | 1.1976 |
| Charlie Kimball | 1.1905 |
| Takuma Sato | 0.9804 |
| Danica Patrick | 0.8696 |
