Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
185/65r14 vs 205/40r17 Tire Comparison Side By Side
  185/65-14 205/40-17 Difference
Diameter inches (mm) 23.47 (596.1) 23.46 (595.8) -0.01 (-0.3) -0.1%
Width inches (mm) 7.28 (185) 8.07 (205) 0.79 (20) 10.8%
Circum. inches (mm) 73.73 (1872.7) 73.69 (1871.76) -0.04 (-0.94) -0.1%
Sidewall Height inches (mm) 4.73 (120.25) 3.23 (82) -1.51 (-38.25) -31.8%
Revolutions per mile (km) 859.37 (533.99) 859.8 (534.26) 0.43 (0.27) 0.1%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.99 mph (32.17 km/h)
25 mph (40.23 km/h)24.99 mph (40.21 km/h)
30 mph (48.28 km/h)29.98 mph (48.26 km/h)
35 mph (56.33 km/h)34.98 mph (56.3 km/h)
40 mph (64.37 km/h)39.98 mph (64.34 km/h)
45 mph (72.42 km/h)44.98 mph (72.38 km/h)
50 mph (80.47 km/h)49.97 mph (80.43 km/h)
55 mph (88.51 km/h)54.97 mph (88.47 km/h)
60 mph (96.56 km/h)59.97 mph (96.51 km/h)
65 mph (104.61 km/h)64.97 mph (104.55 km/h)
70 mph (112.65 km/h)69.96 mph (112.6 km/h)
75 mph (120.7 km/h)74.96 mph (120.64 km/h)
80 mph (128.75 km/h)79.96 mph (128.68 km/h)
85 mph (136.79 km/h)84.96 mph (136.73 km/h)
90 mph (144.84 km/h)89.95 mph (144.77 km/h)
95 mph (152.89 km/h)94.95 mph (152.81 km/h)
100 mph (160.93 km/h)99.95 mph (160.85 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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