Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
135/80r12 vs 135/50r14 Tire Comparison Side By Side
  135/80-12 135/50-14 Difference
Diameter inches (mm) 20.5 (520.8) 19.31 (490.6) -1.19 (-30.2) -5.8%
Width inches (mm) 5.31 (135) 5.31 (135) 0 (0) 0%
Circum. inches (mm) 64.42 (1636.14) 60.68 (1541.27) -3.74 (-94.88) -5.8%
Sidewall Height inches (mm) 4.25 (108) 2.66 (67.5) -1.59 (-40.5) -37.5%
Revolutions per mile (km) 983.62 (611.19) 1044.17 (648.82) 60.55 (37.62) 6.2%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)18.84 mph (30.32 km/h)
25 mph (40.23 km/h)23.55 mph (37.9 km/h)
30 mph (48.28 km/h)28.26 mph (45.48 km/h)
35 mph (56.33 km/h)32.97 mph (53.06 km/h)
40 mph (64.37 km/h)37.68 mph (60.64 km/h)
45 mph (72.42 km/h)42.39 mph (68.22 km/h)
50 mph (80.47 km/h)47.1 mph (75.8 km/h)
55 mph (88.51 km/h)51.81 mph (83.38 km/h)
60 mph (96.56 km/h)56.52 mph (90.96 km/h)
65 mph (104.61 km/h)61.23 mph (98.54 km/h)
70 mph (112.65 km/h)65.94 mph (106.12 km/h)
75 mph (120.7 km/h)70.65 mph (113.7 km/h)
80 mph (128.75 km/h)75.36 mph (121.28 km/h)
85 mph (136.79 km/h)80.07 mph (128.86 km/h)
90 mph (144.84 km/h)84.78 mph (136.44 km/h)
95 mph (152.89 km/h)89.49 mph (144.02 km/h)
100 mph (160.93 km/h)94.2 mph (151.6 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 135/80-R12 Comparisons

To Top