Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
245/60r18 vs 285/45r20 Tire Comparison Side By Side
  245/60-18 285/45-20 Difference
Diameter inches (mm) 29.57 (751.2) 30.1 (764.5) 0.52 (13.3) 1.8%
Width inches (mm) 9.65 (245) 11.22 (285) 1.57 (40) 16.3%
Circum. inches (mm) 92.91 (2359.96) 94.56 (2401.75) 1.65 (41.78) 1.8%
Sidewall Height inches (mm) 5.79 (147) 5.05 (128.25) -0.74 (-18.75) -12.8%
Revolutions per mile (km) 681.94 (423.73) 670.07 (416.36) -11.86 (-7.37) -1.7%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.35 mph (32.76 km/h)
25 mph (40.23 km/h)25.44 mph (40.95 km/h)
30 mph (48.28 km/h)30.53 mph (49.14 km/h)
35 mph (56.33 km/h)35.62 mph (57.32 km/h)
40 mph (64.37 km/h)40.71 mph (65.51 km/h)
45 mph (72.42 km/h)45.8 mph (73.7 km/h)
50 mph (80.47 km/h)50.89 mph (81.89 km/h)
55 mph (88.51 km/h)55.97 mph (90.08 km/h)
60 mph (96.56 km/h)61.06 mph (98.27 km/h)
65 mph (104.61 km/h)66.15 mph (106.46 km/h)
70 mph (112.65 km/h)71.24 mph (114.65 km/h)
75 mph (120.7 km/h)76.33 mph (122.84 km/h)
80 mph (128.75 km/h)81.42 mph (131.03 km/h)
85 mph (136.79 km/h)86.5 mph (139.22 km/h)
90 mph (144.84 km/h)91.59 mph (147.41 km/h)
95 mph (152.89 km/h)96.68 mph (155.59 km/h)
100 mph (160.93 km/h)101.77 mph (163.78 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
17051981213322282329240224822576270728372982309833093541372238393904414344775203
Better Fuel Economy Factory Ratios Increased Power

Most Popular 245/60-R18 Comparisons

To Top