Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 225/45-21 | 255/65-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.97 (735.9) | 31.05 (788.7) | 2.08 (52.8) 7.2% |
| Width inches (mm) | 8.86 (225) | 10.04 (255) | 1.18 (30) 13.3% |
| Circum. inches (mm) | 91.02 (2311.9) | 97.55 (2477.77) | 6.53 (165.88) 7.2% |
| Sidewall Height inches (mm) | 3.99 (101.25) | 6.53 (165.75) | 2.54 (64.5) 63.7% |
| Revolutions per mile (km) | 696.11 (432.54) | 649.51 (403.59) | -46.6 (-28.96) -6.7% |
255/65-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.43 mph (34.5 km/h) |
| 25 mph (40.23 km/h) | 26.79 mph (43.12 km/h) |
| 30 mph (48.28 km/h) | 32.15 mph (51.74 km/h) |
| 35 mph (56.33 km/h) | 37.51 mph (60.37 km/h) |
| 40 mph (64.37 km/h) | 42.87 mph (68.99 km/h) |
| 45 mph (72.42 km/h) | 48.23 mph (77.62 km/h) |
| 50 mph (80.47 km/h) | 53.59 mph (86.24 km/h) |
| 55 mph (88.51 km/h) | 58.95 mph (94.86 km/h) |
| 60 mph (96.56 km/h) | 64.3 mph (103.49 km/h) |
| 65 mph (104.61 km/h) | 69.66 mph (112.11 km/h) |
| 70 mph (112.65 km/h) | 75.02 mph (120.74 km/h) |
| 75 mph (120.7 km/h) | 80.38 mph (129.36 km/h) |
| 80 mph (128.75 km/h) | 85.74 mph (137.99 km/h) |
| 85 mph (136.79 km/h) | 91.1 mph (146.61 km/h) |
| 90 mph (144.84 km/h) | 96.46 mph (155.23 km/h) |
| 95 mph (152.89 km/h) | 101.82 mph (163.86 km/h) |
| 100 mph (160.93 km/h) | 107.17 mph (172.48 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1653 | 1920 | 2068 | 2159 | 2258 | 2328 | 2405 | 2497 | 2624 | 2750 | 2891 | 3003 | 3207 | 3432 | 3608 | 3721 | 3784 | 4016 | 4340 | 5043 |
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