Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
100/70r12 vs 120/70r10 Tire Comparison Side By Side
  100/70-12 120/70-10 Difference
Diameter inches (mm) 17.51 (444.8) 16.61 (422) -0.9 (-22.8) -5.1%
Width inches (mm) 3.94 (100) 4.72 (120) 0.79 (20) 20%
Circum. inches (mm) 55.01 (1397.38) 52.19 (1325.75) -2.82 (-71.63) -5.1%
Sidewall Height inches (mm) 2.76 (70) 3.31 (84) 0.55 (14) 20%
Revolutions per mile (km) 1151.69 (715.62) 1213.91 (754.29) 62.22 (38.66) 5.4%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)18.97 mph (30.54 km/h)
25 mph (40.23 km/h)23.72 mph (38.17 km/h)
30 mph (48.28 km/h)28.46 mph (45.81 km/h)
35 mph (56.33 km/h)33.21 mph (53.44 km/h)
40 mph (64.37 km/h)37.95 mph (61.07 km/h)
45 mph (72.42 km/h)42.69 mph (68.71 km/h)
50 mph (80.47 km/h)47.44 mph (76.34 km/h)
55 mph (88.51 km/h)52.18 mph (83.98 km/h)
60 mph (96.56 km/h)56.92 mph (91.61 km/h)
65 mph (104.61 km/h)61.67 mph (99.25 km/h)
70 mph (112.65 km/h)66.41 mph (106.88 km/h)
75 mph (120.7 km/h)71.16 mph (114.51 km/h)
80 mph (128.75 km/h)75.9 mph (122.15 km/h)
85 mph (136.79 km/h)80.64 mph (129.78 km/h)
90 mph (144.84 km/h)85.39 mph (137.42 km/h)
95 mph (152.89 km/h)90.13 mph (145.05 km/h)
100 mph (160.93 km/h)94.87 mph (152.69 km/h)

Gear Ratio / RPMs for New Tire (@ 65 mph)
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
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
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