Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
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100/70r12 vs 100/60r12 Tire Comparison Side By Side
  100/70-12 100/60-12 Difference
Diameter inches (mm) 17.51 (444.8) 16.72 (424.8) -0.79 (-20) -4.5%
Width inches (mm) 3.94 (100) 3.94 (100) 0 (0) 0%
Circum. inches (mm) 55.01 (1397.38) 52.54 (1334.55) -2.47 (-62.83) -4.5%
Sidewall Height inches (mm) 2.76 (70) 2.36 (60) -0.39 (-10) -14.3%
Revolutions per mile (km) 1151.69 (715.62) 1205.91 (749.32) 54.22 (33.69) 4.7%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.1 mph (30.74 km/h)
25 mph (40.23 km/h)23.88 mph (38.42 km/h)
30 mph (48.28 km/h)28.65 mph (46.11 km/h)
35 mph (56.33 km/h)33.43 mph (53.79 km/h)
40 mph (64.37 km/h)38.2 mph (61.48 km/h)
45 mph (72.42 km/h)42.98 mph (69.16 km/h)
50 mph (80.47 km/h)47.75 mph (76.85 km/h)
55 mph (88.51 km/h)52.53 mph (84.53 km/h)
60 mph (96.56 km/h)57.3 mph (92.22 km/h)
65 mph (104.61 km/h)62.08 mph (99.9 km/h)
70 mph (112.65 km/h)66.85 mph (107.59 km/h)
75 mph (120.7 km/h)71.63 mph (115.27 km/h)
80 mph (128.75 km/h)76.4 mph (122.96 km/h)
85 mph (136.79 km/h)81.18 mph (130.64 km/h)
90 mph (144.84 km/h)85.95 mph (138.33 km/h)
95 mph (152.89 km/h)90.73 mph (146.01 km/h)
100 mph (160.93 km/h)95.5 mph (153.7 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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