Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/65-20 | 33/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 35.61 (904.5) | 33.02 (838.72) | -2.59 (-65.78) -7.3% |
| Width inches (mm) | 12.01 (305) | 12.52 (318) | 0.51 (13) 4.3% |
| Circum. inches (mm) | 111.87 (2841.57) | 103.74 (2634.92) | -8.14 (-206.65) -7.3% |
| Sidewall Height inches (mm) | 7.81 (198.25) | 6.51 (165.36) | -1.29 (-32.89) -16.6% |
| Revolutions per mile (km) | 566.36 (351.92) | 610.78 (379.52) | 44.42 (27.6) 7.8% |
33/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.55 mph (29.85 km/h) |
| 25 mph (40.23 km/h) | 23.18 mph (37.31 km/h) |
| 30 mph (48.28 km/h) | 27.82 mph (44.77 km/h) |
| 35 mph (56.33 km/h) | 32.45 mph (52.23 km/h) |
| 40 mph (64.37 km/h) | 37.09 mph (59.69 km/h) |
| 45 mph (72.42 km/h) | 41.73 mph (67.15 km/h) |
| 50 mph (80.47 km/h) | 46.36 mph (74.62 km/h) |
| 55 mph (88.51 km/h) | 51 mph (82.08 km/h) |
| 60 mph (96.56 km/h) | 55.64 mph (89.54 km/h) |
| 65 mph (104.61 km/h) | 60.27 mph (97 km/h) |
| 70 mph (112.65 km/h) | 64.91 mph (104.46 km/h) |
| 75 mph (120.7 km/h) | 69.55 mph (111.92 km/h) |
| 80 mph (128.75 km/h) | 74.18 mph (119.38 km/h) |
| 85 mph (136.79 km/h) | 78.82 mph (126.85 km/h) |
| 90 mph (144.84 km/h) | 83.45 mph (134.31 km/h) |
| 95 mph (152.89 km/h) | 88.09 mph (141.77 km/h) |
| 100 mph (160.93 km/h) | 92.73 mph (149.23 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1554 | 1806 | 1945 | 2031 | 2123 | 2189 | 2262 | 2348 | 2467 | 2586 | 2718 | 2824 | 3016 | 3228 | 3393 | 3499 | 3558 | 3777 | 4081 | 4742 |
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