La NASCAR vient de dévoiler la longueur des segments pour toutes les courses de la saison 2021. Les segments concernant les épreuves de Cup, Xfinity et Trucks ont été publiés.
Il ne manquent que les informations pour les courses routières sur le Circuit des Amériques et la All-Star Race sur le Texas Motor Speedway.
Ci-dessous le détail des segments pour les courses de NASCAR Cup Series en 2021.
NASCAR CUP SERIES
| Circuit | Segment 1 | Segment 2 | Arrivée |
| Daytona International Speedway | 65 | 130 | 200 |
| Daytona International Speedway Road Course | 16 | 34 | 70 |
| Homestead-Miami Speedway | 80 | 160 | 267 |
| Las Vegas Motor Speedway | 80 | 160 | 267 |
| Phoenix Raceway | 75 | 190 | 312 |
| Atlanta Motor Speedway | 105 | 210 | 325 |
| Bristol Motor Speedway (Dirt) | 75 | 150 | 250 |
| Martinsville Speedway | 130 | 260 | 500 |
| Richmond Raceway | 80 | 235 | 400 |
| Talladega Superspeedway | 60 | 120 | 188 |
| Kansas Speedway | 80 | 160 | 267 |
| Darlington Speedway | 90 | 185 | 293 |
| Dover International Speedway | 120 | 240 | 400 |
| Circuit of the Americas | – | – | – |
| Charlotte Motor Speedway | 100 | 200 | Segment 3: 300 / Arrivée: 400 |
| Sonoma Raceway | 20 | 40 | 90 |
| Texas Motor Speedway (All-Star Race) | – | – | – |
| Nashville Superspeedway | 90 | 185 | 300 |
| Pocono Raceway | 25 | 77 | 130 |
| Pocono Raceway | 30 | 85 | 140 |
| Road America | 14 | 29 | 62 |
| Atlanta Motor Speedway | 80 | 160 | 260 |
| New Hampshire Motor Speedway | 75 | 185 | 301 |
| Watkins Glen International | 20 | 40 | 90 |
| Indianapolis Motor Speedway Road Course | 15 | 35 | 82 |
| Michigan International Speedway | 60 | 120 | 200 |
| Daytona International Speedway | 50 | 100 | 160 |
| *Darlington Raceway | 115 | 230 | 367 |
| *Richmond Raceway | 80 | 235 | 400 |
| *Bristol Motor Speedway | 125 | 250 | 500 |
| *Las Vegas Motor Speedway | 80 | 160 | 267 |
| *Talladega Superspeedway | 60 | 120 | 188 |
| *Charlotte Motor Speedway Roval | 25 | 50 | 109 |
| *Texas Motor Speedway | 105 | 210 | 334 |
| *Kansas Speedway | 80 | 160 | 267 |
| *Martinsville Speedway | 130 | 260 | 500 |
| *Phoenix Raceway | 75 | 190 | 312 |
