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 245/35r20 Tire Comparison Side By Side
  355/25-21 245/35-20 Difference
Diameter inches (mm) 27.99 (710.9) 26.75 (679.5) -1.24 (-31.4) -4.4%
Width inches (mm) 13.98 (355) 9.65 (245) -4.33 (-110) -31%
Circum. inches (mm) 87.93 (2233.36) 84.04 (2134.71) -3.88 (-98.65) -4.4%
Sidewall Height inches (mm) 3.49 (88.75) 3.38 (85.75) -0.12 (-3) -3.4%
Revolutions per mile (km) 720.59 (447.76) 753.89 (468.45) 33.3 (20.69) 4.6%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.12 mph (30.77 km/h)
25 mph (40.23 km/h)23.9 mph (38.46 km/h)
30 mph (48.28 km/h)28.67 mph (46.15 km/h)
35 mph (56.33 km/h)33.45 mph (53.84 km/h)
40 mph (64.37 km/h)38.23 mph (61.53 km/h)
45 mph (72.42 km/h)43.01 mph (69.22 km/h)
50 mph (80.47 km/h)47.79 mph (76.91 km/h)
55 mph (88.51 km/h)52.57 mph (84.6 km/h)
60 mph (96.56 km/h)57.35 mph (92.3 km/h)
65 mph (104.61 km/h)62.13 mph (99.99 km/h)
70 mph (112.65 km/h)66.91 mph (107.68 km/h)
75 mph (120.7 km/h)71.69 mph (115.37 km/h)
80 mph (128.75 km/h)76.47 mph (123.06 km/h)
85 mph (136.79 km/h)81.25 mph (130.75 km/h)
90 mph (144.84 km/h)86.02 mph (138.44 km/h)
95 mph (152.89 km/h)90.8 mph (146.14 km/h)
100 mph (160.93 km/h)95.58 mph (153.83 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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