Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
235/40r20 vs 255/40r20 Tire Comparison Side By Side
  235/40-20 255/40-20 Difference
Diameter inches (mm) 27.4 (696) 28.03 (712) 0.63 (16) 2.3%
Width inches (mm) 9.25 (235) 10.04 (255) 0.79 (20) 8.5%
Circum. inches (mm) 86.08 (2186.55) 88.06 (2236.81) 1.98 (50.27) 2.3%
Sidewall Height inches (mm) 3.7 (94) 4.02 (102) 0.31 (8) 8.5%
Revolutions per mile (km) 736.02 (457.34) 719.48 (447.06) -16.54 (-10.28) -2.2%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.46 mph (32.93 km/h)
25 mph (40.23 km/h)25.57 mph (41.16 km/h)
30 mph (48.28 km/h)30.69 mph (49.39 km/h)
35 mph (56.33 km/h)35.8 mph (57.62 km/h)
40 mph (64.37 km/h)40.92 mph (65.85 km/h)
45 mph (72.42 km/h)46.03 mph (74.09 km/h)
50 mph (80.47 km/h)51.15 mph (82.32 km/h)
55 mph (88.51 km/h)56.26 mph (90.55 km/h)
60 mph (96.56 km/h)61.38 mph (98.78 km/h)
65 mph (104.61 km/h)66.49 mph (107.01 km/h)
70 mph (112.65 km/h)71.61 mph (115.24 km/h)
75 mph (120.7 km/h)76.72 mph (123.48 km/h)
80 mph (128.75 km/h)81.84 mph (131.71 km/h)
85 mph (136.79 km/h)86.95 mph (139.94 km/h)
90 mph (144.84 km/h)92.07 mph (148.17 km/h)
95 mph (152.89 km/h)97.18 mph (156.4 km/h)
100 mph (160.93 km/h)102.3 mph (164.63 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
18312127229123922501257926652766290630463202332735533802399741224192444948075586
Better Fuel Economy Factory Ratios Increased Power

Most Popular 235/40-R20 Comparisons

To Top