Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
355/25r21 vs 355/40r22.5 Tire Comparison Side By Side
  355/25-21 355/40-22.5 Difference
Diameter inches (mm) 27.99 (710.9) 33.68 (855.5) 5.69 (144.6) 20.3%
Width inches (mm) 13.98 (355) 13.98 (355) 0 (0) 0%
Circum. inches (mm) 87.93 (2233.36) 105.81 (2687.63) 17.88 (454.27) 20.3%
Sidewall Height inches (mm) 3.49 (88.75) 5.59 (142) 2.1 (53.25) 60%
Revolutions per mile (km) 720.59 (447.76) 598.8 (372.07) -121.8 (-75.68) -16.9%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)24.07 mph (38.73 km/h)
25 mph (40.23 km/h)30.09 mph (48.42 km/h)
30 mph (48.28 km/h)36.1 mph (58.1 km/h)
35 mph (56.33 km/h)42.12 mph (67.78 km/h)
40 mph (64.37 km/h)48.14 mph (77.47 km/h)
45 mph (72.42 km/h)54.15 mph (87.15 km/h)
50 mph (80.47 km/h)60.17 mph (96.83 km/h)
55 mph (88.51 km/h)66.19 mph (106.52 km/h)
60 mph (96.56 km/h)72.2 mph (116.2 km/h)
65 mph (104.61 km/h)78.22 mph (125.89 km/h)
70 mph (112.65 km/h)84.24 mph (135.57 km/h)
75 mph (120.7 km/h)90.26 mph (145.25 km/h)
80 mph (128.75 km/h)96.27 mph (154.94 km/h)
85 mph (136.79 km/h)102.29 mph (164.62 km/h)
90 mph (144.84 km/h)108.31 mph (174.3 km/h)
95 mph (152.89 km/h)114.32 mph (183.99 km/h)
100 mph (160.93 km/h)120.34 mph (193.67 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
15241770190619912081214622182302241925352665276929573164332634303489370340014649
Better Fuel Economy Factory Ratios Increased Power

Most Popular 355/25-R21 Comparisons

To Top