Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
155/80r15 vs 145/80r15 Tire Comparison Side By Side
  155/80-15 145/80-15 Difference
Diameter inches (mm) 24.76 (629) 24.13 (613) -0.63 (-16) -2.5%
Width inches (mm) 6.1 (155) 5.71 (145) -0.39 (-10) -6.5%
Circum. inches (mm) 77.8 (1976.06) 75.82 (1925.8) -1.98 (-50.27) -2.5%
Sidewall Height inches (mm) 4.88 (124) 4.57 (116) -0.31 (-8) -6.5%
Revolutions per mile (km) 814.42 (506.06) 835.68 (519.26) 21.26 (13.21) 2.6%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.49 mph (31.37 km/h)
25 mph (40.23 km/h)24.36 mph (39.21 km/h)
30 mph (48.28 km/h)29.24 mph (47.05 km/h)
35 mph (56.33 km/h)34.11 mph (54.89 km/h)
40 mph (64.37 km/h)38.98 mph (62.74 km/h)
45 mph (72.42 km/h)43.86 mph (70.58 km/h)
50 mph (80.47 km/h)48.73 mph (78.42 km/h)
55 mph (88.51 km/h)53.6 mph (86.26 km/h)
60 mph (96.56 km/h)58.47 mph (94.1 km/h)
65 mph (104.61 km/h)63.35 mph (101.95 km/h)
70 mph (112.65 km/h)68.22 mph (109.79 km/h)
75 mph (120.7 km/h)73.09 mph (117.63 km/h)
80 mph (128.75 km/h)77.97 mph (125.47 km/h)
85 mph (136.79 km/h)82.84 mph (133.31 km/h)
90 mph (144.84 km/h)87.71 mph (141.16 km/h)
95 mph (152.89 km/h)92.58 mph (149 km/h)
100 mph (160.93 km/h)97.46 mph (156.84 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
21272471266127782905299530953213337535383719386441274416464247874869516755846489
Better Fuel Economy Factory Ratios Increased Power

Most Popular 155/80-R15 Comparisons

To Top