Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
125/90r15 vs 275/70r18 Tire Comparison Side By Side
  125/90-15 275/70-18 Difference
Diameter inches (mm) 23.86 (606) 33.16 (842.2) 9.3 (236.2) 39%
Width inches (mm) 4.92 (125) 10.83 (275) 5.91 (150) 120%
Circum. inches (mm) 74.95 (1903.81) 104.17 (2645.85) 29.21 (742.04) 39%
Sidewall Height inches (mm) 4.43 (112.5) 7.58 (192.5) 3.15 (80) 71.1%
Revolutions per mile (km) 845.33 (525.26) 608.25 (377.95) -237.08 (-147.31) -28%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)27.8 mph (44.73 km/h)
25 mph (40.23 km/h)34.74 mph (55.92 km/h)
30 mph (48.28 km/h)41.69 mph (67.1 km/h)
35 mph (56.33 km/h)48.64 mph (78.28 km/h)
40 mph (64.37 km/h)55.59 mph (89.46 km/h)
45 mph (72.42 km/h)62.54 mph (100.65 km/h)
50 mph (80.47 km/h)69.49 mph (111.83 km/h)
55 mph (88.51 km/h)76.44 mph (123.01 km/h)
60 mph (96.56 km/h)83.39 mph (134.2 km/h)
65 mph (104.61 km/h)90.33 mph (145.38 km/h)
70 mph (112.65 km/h)97.28 mph (156.56 km/h)
75 mph (120.7 km/h)104.23 mph (167.75 km/h)
80 mph (128.75 km/h)111.18 mph (178.93 km/h)
85 mph (136.79 km/h)118.13 mph (190.11 km/h)
90 mph (144.84 km/h)125.08 mph (201.3 km/h)
95 mph (152.89 km/h)132.03 mph (212.48 km/h)
100 mph (160.93 km/h)138.98 mph (223.66 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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