Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
155/70r15 vs 100/70r15 Tire Comparison Side By Side
  155/70-15 100/70-15 Difference
Diameter inches (mm) 23.54 (598) 20.51 (521) -3.03 (-77) -12.9%
Width inches (mm) 6.1 (155) 3.94 (100) -2.17 (-55) -35.5%
Circum. inches (mm) 73.96 (1878.67) 64.44 (1636.77) -9.52 (-241.9) -12.9%
Sidewall Height inches (mm) 4.27 (108.5) 2.76 (70) -1.52 (-38.5) -35.5%
Revolutions per mile (km) 856.64 (532.29) 983.24 (610.96) 126.6 (78.67) 14.8%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)17.42 mph (28.04 km/h)
25 mph (40.23 km/h)21.78 mph (35.05 km/h)
30 mph (48.28 km/h)26.14 mph (42.06 km/h)
35 mph (56.33 km/h)30.49 mph (49.07 km/h)
40 mph (64.37 km/h)34.85 mph (56.08 km/h)
45 mph (72.42 km/h)39.21 mph (63.1 km/h)
50 mph (80.47 km/h)43.56 mph (70.11 km/h)
55 mph (88.51 km/h)47.92 mph (77.12 km/h)
60 mph (96.56 km/h)52.27 mph (84.13 km/h)
65 mph (104.61 km/h)56.63 mph (91.14 km/h)
70 mph (112.65 km/h)60.99 mph (98.15 km/h)
75 mph (120.7 km/h)65.34 mph (105.16 km/h)
80 mph (128.75 km/h)69.7 mph (112.17 km/h)
85 mph (136.79 km/h)74.06 mph (119.18 km/h)
90 mph (144.84 km/h)78.41 mph (126.19 km/h)
95 mph (152.89 km/h)82.77 mph (133.2 km/h)
100 mph (160.93 km/h)87.12 mph (140.21 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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