Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
120/70r19 vs 90/90r21 Tire Comparison Side By Side
  120/70-19 90/90-21 Difference
Diameter inches (mm) 25.61 (650.6) 27.38 (695.4) 1.76 (44.8) 6.9%
Width inches (mm) 4.72 (120) 3.54 (90) -1.18 (-30) -25%
Circum. inches (mm) 80.47 (2043.92) 86.01 (2184.66) 5.54 (140.74) 6.9%
Sidewall Height inches (mm) 3.31 (84) 3.19 (81) -0.12 (-3) -3.6%
Revolutions per mile (km) 787.38 (489.25) 736.66 (457.74) -50.73 (-31.52) -6.4%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)21.38 mph (34.4 km/h)
25 mph (40.23 km/h)26.72 mph (43 km/h)
30 mph (48.28 km/h)32.07 mph (51.6 km/h)
35 mph (56.33 km/h)37.41 mph (60.21 km/h)
40 mph (64.37 km/h)42.75 mph (68.81 km/h)
45 mph (72.42 km/h)48.1 mph (77.41 km/h)
50 mph (80.47 km/h)53.44 mph (86.01 km/h)
55 mph (88.51 km/h)58.79 mph (94.61 km/h)
60 mph (96.56 km/h)64.13 mph (103.21 km/h)
65 mph (104.61 km/h)69.48 mph (111.81 km/h)
70 mph (112.65 km/h)74.82 mph (120.41 km/h)
75 mph (120.7 km/h)80.16 mph (129.01 km/h)
80 mph (128.75 km/h)85.51 mph (137.61 km/h)
85 mph (136.79 km/h)90.85 mph (146.21 km/h)
90 mph (144.84 km/h)96.2 mph (154.81 km/h)
95 mph (152.89 km/h)101.54 mph (163.42 km/h)
100 mph (160.93 km/h)106.89 mph (172.02 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
18752178234524492561264027282832297631193279340636383893409242204292455549225720
Better Fuel Economy Factory Ratios Increased Power

Most Popular 120/70-R19 Comparisons

To Top