Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
185/55r15 vs 205/50r15 Tire Comparison Side By Side
  185/55-15 205/50-15 Difference
Diameter inches (mm) 23.01 (584.5) 23.07 (586) 0.06 (1.5) 0.3%
Width inches (mm) 7.28 (185) 8.07 (205) 0.79 (20) 10.8%
Circum. inches (mm) 72.29 (1836.26) 72.48 (1840.97) 0.19 (4.71) 0.3%
Sidewall Height inches (mm) 4.01 (101.75) 4.04 (102.5) 0.03 (0.75) 0.7%
Revolutions per mile (km) 876.42 (544.58) 874.18 (543.19) -2.24 (-1.39) -0.3%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.05 mph (32.27 km/h)
25 mph (40.23 km/h)25.06 mph (40.34 km/h)
30 mph (48.28 km/h)30.08 mph (48.4 km/h)
35 mph (56.33 km/h)35.09 mph (56.47 km/h)
40 mph (64.37 km/h)40.1 mph (64.54 km/h)
45 mph (72.42 km/h)45.12 mph (72.61 km/h)
50 mph (80.47 km/h)50.13 mph (80.67 km/h)
55 mph (88.51 km/h)55.14 mph (88.74 km/h)
60 mph (96.56 km/h)60.15 mph (96.81 km/h)
65 mph (104.61 km/h)65.17 mph (104.88 km/h)
70 mph (112.65 km/h)70.18 mph (112.94 km/h)
75 mph (120.7 km/h)75.19 mph (121.01 km/h)
80 mph (128.75 km/h)80.21 mph (129.08 km/h)
85 mph (136.79 km/h)85.22 mph (137.15 km/h)
90 mph (144.84 km/h)90.23 mph (145.21 km/h)
95 mph (152.89 km/h)95.24 mph (153.28 km/h)
100 mph (160.93 km/h)100.26 mph (161.35 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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