Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
225/45r13 vs 205/50r13 Tire Comparison Side By Side
  225/45-13 205/50-13 Difference
Diameter inches (mm) 20.97 (532.7) 21.07 (535.2) 0.1 (2.5) 0.5%
Width inches (mm) 8.86 (225) 8.07 (205) -0.79 (-20) -8.9%
Circum. inches (mm) 65.89 (1673.53) 66.2 (1681.38) 0.31 (7.85) 0.5%
Sidewall Height inches (mm) 3.99 (101.25) 4.04 (102.5) 0.05 (1.25) 1.2%
Revolutions per mile (km) 961.65 (597.54) 957.16 (594.75) -4.49 (-2.79) -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)35.16 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)50.23 mph (80.84 km/h)
55 mph (88.51 km/h)55.26 mph (88.93 km/h)
60 mph (96.56 km/h)60.28 mph (97.01 km/h)
65 mph (104.61 km/h)65.31 mph (105.1 km/h)
70 mph (112.65 km/h)70.33 mph (113.18 km/h)
75 mph (120.7 km/h)75.35 mph (121.27 km/h)
80 mph (128.75 km/h)80.38 mph (129.35 km/h)
85 mph (136.79 km/h)85.4 mph (137.44 km/h)
90 mph (144.84 km/h)90.42 mph (145.52 km/h)
95 mph (152.89 km/h)95.45 mph (153.61 km/h)
100 mph (160.93 km/h)100.47 mph (161.69 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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