Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
125/70r15 vs 175/70r14 Tire Comparison Side By Side
  125/70-15 175/70-14 Difference
Diameter inches (mm) 21.89 (556) 23.65 (600.6) 1.76 (44.6) 8%
Width inches (mm) 4.92 (125) 6.89 (175) 1.97 (50) 40%
Circum. inches (mm) 68.77 (1746.73) 74.29 (1886.84) 5.52 (140.12) 8%
Sidewall Height inches (mm) 3.44 (87.5) 4.82 (122.5) 1.38 (35) 40%
Revolutions per mile (km) 921.35 (572.5) 852.93 (529.99) -68.42 (-42.51) -7.4%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)21.6 mph (34.77 km/h)
25 mph (40.23 km/h)27.01 mph (43.46 km/h)
30 mph (48.28 km/h)32.41 mph (52.15 km/h)
35 mph (56.33 km/h)37.81 mph (60.85 km/h)
40 mph (64.37 km/h)43.21 mph (69.54 km/h)
45 mph (72.42 km/h)48.61 mph (78.23 km/h)
50 mph (80.47 km/h)54.01 mph (86.92 km/h)
55 mph (88.51 km/h)59.41 mph (95.61 km/h)
60 mph (96.56 km/h)64.81 mph (104.31 km/h)
65 mph (104.61 km/h)70.21 mph (113 km/h)
70 mph (112.65 km/h)75.62 mph (121.69 km/h)
75 mph (120.7 km/h)81.02 mph (130.38 km/h)
80 mph (128.75 km/h)86.42 mph (139.08 km/h)
85 mph (136.79 km/h)91.82 mph (147.77 km/h)
90 mph (144.84 km/h)97.22 mph (156.46 km/h)
95 mph (152.89 km/h)102.62 mph (165.15 km/h)
100 mph (160.93 km/h)108.02 mph (173.84 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
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