Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
100/90r12 vs 120/90r10 Tire Comparison Side By Side
  100/90-12 120/90-10 Difference
Diameter inches (mm) 19.09 (484.8) 18.5 (470) -0.58 (-14.8) -3.1%
Width inches (mm) 3.94 (100) 4.72 (120) 0.79 (20) 20%
Circum. inches (mm) 59.96 (1523.04) 58.13 (1476.55) -1.83 (-46.5) -3.1%
Sidewall Height inches (mm) 3.54 (90) 4.25 (108) 0.71 (18) 20%
Revolutions per mile (km) 1056.66 (656.58) 1089.94 (677.25) 33.27 (20.68) 3.1%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.39 mph (31.2 km/h)
25 mph (40.23 km/h)24.24 mph (39.01 km/h)
30 mph (48.28 km/h)29.08 mph (46.81 km/h)
35 mph (56.33 km/h)33.93 mph (54.61 km/h)
40 mph (64.37 km/h)38.78 mph (62.41 km/h)
45 mph (72.42 km/h)43.63 mph (70.21 km/h)
50 mph (80.47 km/h)48.47 mph (78.01 km/h)
55 mph (88.51 km/h)53.32 mph (85.81 km/h)
60 mph (96.56 km/h)58.17 mph (93.61 km/h)
65 mph (104.61 km/h)63.02 mph (101.41 km/h)
70 mph (112.65 km/h)67.86 mph (109.22 km/h)
75 mph (120.7 km/h)72.71 mph (117.02 km/h)
80 mph (128.75 km/h)77.56 mph (124.82 km/h)
85 mph (136.79 km/h)82.41 mph (132.62 km/h)
90 mph (144.84 km/h)87.25 mph (140.42 km/h)
95 mph (152.89 km/h)92.1 mph (148.22 km/h)
100 mph (160.93 km/h)96.95 mph (156.02 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
Better Fuel Economy Factory Ratios Increased Power

Most Popular 100/90-R12 Comparisons

To Top