Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
355/25r21 vs 245/70r16 Tire Comparison Side By Side
  355/25-21 245/70-16 Difference
Diameter inches (mm) 27.99 (710.9) 29.5 (749.4) 1.52 (38.5) 5.4%
Width inches (mm) 13.98 (355) 9.65 (245) -4.33 (-110) -31%
Circum. inches (mm) 87.93 (2233.36) 92.69 (2354.31) 4.76 (120.95) 5.4%
Sidewall Height inches (mm) 3.49 (88.75) 6.75 (171.5) 3.26 (82.75) 93.2%
Revolutions per mile (km) 720.59 (447.76) 683.57 (424.75) -37.02 (-23) -5.1%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)21.08 mph (33.93 km/h)
25 mph (40.23 km/h)26.35 mph (42.41 km/h)
30 mph (48.28 km/h)31.62 mph (50.9 km/h)
35 mph (56.33 km/h)36.9 mph (59.38 km/h)
40 mph (64.37 km/h)42.17 mph (67.86 km/h)
45 mph (72.42 km/h)47.44 mph (76.34 km/h)
50 mph (80.47 km/h)52.71 mph (84.83 km/h)
55 mph (88.51 km/h)57.98 mph (93.31 km/h)
60 mph (96.56 km/h)63.25 mph (101.79 km/h)
65 mph (104.61 km/h)68.52 mph (110.27 km/h)
70 mph (112.65 km/h)73.79 mph (118.76 km/h)
75 mph (120.7 km/h)79.06 mph (127.24 km/h)
80 mph (128.75 km/h)84.33 mph (135.72 km/h)
85 mph (136.79 km/h)89.6 mph (144.2 km/h)
90 mph (144.84 km/h)94.87 mph (152.69 km/h)
95 mph (152.89 km/h)100.14 mph (161.17 km/h)
100 mph (160.93 km/h)105.42 mph (169.65 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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