Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
155/70r12 vs 155/65r14 Tire Comparison Side By Side
  155/70-12 155/65-14 Difference
Diameter inches (mm) 20.54 (521.8) 21.93 (557.1) 1.39 (35.3) 6.8%
Width inches (mm) 6.1 (155) 6.1 (155) 0 (0) 0%
Circum. inches (mm) 64.54 (1639.28) 68.9 (1750.18) 4.37 (110.9) 6.8%
Sidewall Height inches (mm) 4.27 (108.5) 3.97 (100.75) -0.31 (-7.75) -7.1%
Revolutions per mile (km) 981.74 (610.02) 919.53 (571.37) -62.21 (-38.65) -6.3%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)21.35 mph (34.36 km/h)
25 mph (40.23 km/h)26.69 mph (42.96 km/h)
30 mph (48.28 km/h)32.03 mph (51.55 km/h)
35 mph (56.33 km/h)37.37 mph (60.14 km/h)
40 mph (64.37 km/h)42.71 mph (68.73 km/h)
45 mph (72.42 km/h)48.04 mph (77.32 km/h)
50 mph (80.47 km/h)53.38 mph (85.91 km/h)
55 mph (88.51 km/h)58.72 mph (94.5 km/h)
60 mph (96.56 km/h)64.06 mph (103.09 km/h)
65 mph (104.61 km/h)69.4 mph (111.68 km/h)
70 mph (112.65 km/h)74.74 mph (120.28 km/h)
75 mph (120.7 km/h)80.07 mph (128.87 km/h)
80 mph (128.75 km/h)85.41 mph (137.46 km/h)
85 mph (136.79 km/h)90.75 mph (146.05 km/h)
90 mph (144.84 km/h)96.09 mph (154.64 km/h)
95 mph (152.89 km/h)101.43 mph (163.23 km/h)
100 mph (160.93 km/h)106.77 mph (171.82 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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