Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
120/70r15 vs 140/70r14 Tire Comparison Side By Side
  120/70-15 140/70-14 Difference
Diameter inches (mm) 21.61 (549) 21.72 (551.6) 0.1 (2.6) 0.5%
Width inches (mm) 4.72 (120) 5.51 (140) 0.79 (20) 16.7%
Circum. inches (mm) 67.9 (1724.73) 68.22 (1732.9) 0.32 (8.17) 0.5%
Sidewall Height inches (mm) 3.31 (84) 3.86 (98) 0.55 (14) 16.7%
Revolutions per mile (km) 933.1 (579.8) 928.7 (577.07) -4.4 (-2.73) -0.5%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.09 mph (32.34 km/h)
25 mph (40.23 km/h)25.12 mph (40.42 km/h)
30 mph (48.28 km/h)30.14 mph (48.51 km/h)
35 mph (56.33 km/h)35.17 mph (56.59 km/h)
40 mph (64.37 km/h)40.19 mph (64.68 km/h)
45 mph (72.42 km/h)45.21 mph (72.76 km/h)
50 mph (80.47 km/h)50.24 mph (80.85 km/h)
55 mph (88.51 km/h)55.26 mph (88.93 km/h)
60 mph (96.56 km/h)60.28 mph (97.02 km/h)
65 mph (104.61 km/h)65.31 mph (105.1 km/h)
70 mph (112.65 km/h)70.33 mph (113.19 km/h)
75 mph (120.7 km/h)75.36 mph (121.27 km/h)
80 mph (128.75 km/h)80.38 mph (129.36 km/h)
85 mph (136.79 km/h)85.4 mph (137.44 km/h)
90 mph (144.84 km/h)90.43 mph (145.53 km/h)
95 mph (152.89 km/h)95.45 mph (153.61 km/h)
100 mph (160.93 km/h)100.47 mph (161.7 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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