Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
145/85r18 vs 245/50r19 Tire Comparison Side By Side
  145/85-18 245/50-19 Difference
Diameter inches (mm) 27.7 (703.7) 28.65 (727.6) 0.94 (23.9) 3.4%
Width inches (mm) 5.71 (145) 9.65 (245) 3.94 (100) 69%
Circum. inches (mm) 87.04 (2210.74) 89.99 (2285.82) 2.96 (75.08) 3.4%
Sidewall Height inches (mm) 4.85 (123.25) 4.82 (122.5) -0.03 (-0.75) -0.6%
Revolutions per mile (km) 727.97 (452.34) 704.05 (437.48) -23.91 (-14.86) -3.3%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.68 mph (33.28 km/h)
25 mph (40.23 km/h)25.85 mph (41.6 km/h)
30 mph (48.28 km/h)31.02 mph (49.92 km/h)
35 mph (56.33 km/h)36.19 mph (58.24 km/h)
40 mph (64.37 km/h)41.36 mph (66.56 km/h)
45 mph (72.42 km/h)46.53 mph (74.88 km/h)
50 mph (80.47 km/h)51.7 mph (83.2 km/h)
55 mph (88.51 km/h)56.87 mph (91.52 km/h)
60 mph (96.56 km/h)62.04 mph (99.84 km/h)
65 mph (104.61 km/h)67.21 mph (108.16 km/h)
70 mph (112.65 km/h)72.38 mph (116.48 km/h)
75 mph (120.7 km/h)77.55 mph (124.8 km/h)
80 mph (128.75 km/h)82.72 mph (133.12 km/h)
85 mph (136.79 km/h)87.89 mph (141.44 km/h)
90 mph (144.84 km/h)93.06 mph (149.76 km/h)
95 mph (152.89 km/h)98.23 mph (158.08 km/h)
100 mph (160.93 km/h)103.4 mph (166.4 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
17922081224223412447252426072707284429813134325634773721391140334102435347045467
Better Fuel Economy Factory Ratios Increased Power

Most Popular 145/85-R18 Comparisons

To Top