Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
155/80r12 vs 175/80r13 Tire Comparison Side By Side
  155/80-12 175/80-13 Difference
Diameter inches (mm) 21.76 (552.8) 24.02 (610.2) 2.26 (57.4) 10.4%
Width inches (mm) 6.1 (155) 6.89 (175) 0.79 (20) 12.9%
Circum. inches (mm) 68.37 (1736.67) 75.47 (1917) 7.1 (180.33) 10.4%
Sidewall Height inches (mm) 4.88 (124) 5.51 (140) 0.63 (16) 12.9%
Revolutions per mile (km) 926.68 (575.81) 839.51 (521.65) -87.17 (-54.17) -9.4%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)22.08 mph (35.53 km/h)
25 mph (40.23 km/h)27.6 mph (44.41 km/h)
30 mph (48.28 km/h)33.12 mph (53.29 km/h)
35 mph (56.33 km/h)38.63 mph (62.18 km/h)
40 mph (64.37 km/h)44.15 mph (71.06 km/h)
45 mph (72.42 km/h)49.67 mph (79.94 km/h)
50 mph (80.47 km/h)55.19 mph (88.82 km/h)
55 mph (88.51 km/h)60.71 mph (97.7 km/h)
60 mph (96.56 km/h)66.23 mph (106.59 km/h)
65 mph (104.61 km/h)71.75 mph (115.47 km/h)
70 mph (112.65 km/h)77.27 mph (124.35 km/h)
75 mph (120.7 km/h)82.79 mph (133.23 km/h)
80 mph (128.75 km/h)88.31 mph (142.12 km/h)
85 mph (136.79 km/h)93.83 mph (151 km/h)
90 mph (144.84 km/h)99.35 mph (159.88 km/h)
95 mph (152.89 km/h)104.86 mph (168.76 km/h)
100 mph (160.93 km/h)110.38 mph (177.65 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
21362482267327912918300931093227339135553736388241464436466448094891519156096518
Better Fuel Economy Factory Ratios Increased Power

Most Popular 155/80-R12 Comparisons

To Top