Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
265/40r18 vs 255/45r18 Tire Comparison Side By Side
  265/40-18 255/45-18 Difference
Diameter inches (mm) 26.35 (669.2) 27.04 (686.7) 0.69 (17.5) 2.6%
Width inches (mm) 10.43 (265) 10.04 (255) -0.39 (-10) -3.8%
Circum. inches (mm) 82.77 (2102.35) 84.93 (2157.33) 2.16 (54.98) 2.6%
Sidewall Height inches (mm) 4.17 (106) 4.52 (114.75) 0.34 (8.75) 8.3%
Revolutions per mile (km) 765.5 (475.66) 745.99 (463.53) -19.51 (-12.12) -2.5%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.52 mph (33.03 km/h)
25 mph (40.23 km/h)25.65 mph (41.29 km/h)
30 mph (48.28 km/h)30.78 mph (49.54 km/h)
35 mph (56.33 km/h)35.92 mph (57.8 km/h)
40 mph (64.37 km/h)41.05 mph (66.06 km/h)
45 mph (72.42 km/h)46.18 mph (74.31 km/h)
50 mph (80.47 km/h)51.31 mph (82.57 km/h)
55 mph (88.51 km/h)56.44 mph (90.83 km/h)
60 mph (96.56 km/h)61.57 mph (99.09 km/h)
65 mph (104.61 km/h)66.7 mph (107.34 km/h)
70 mph (112.65 km/h)71.83 mph (115.6 km/h)
75 mph (120.7 km/h)76.96 mph (123.86 km/h)
80 mph (128.75 km/h)82.09 mph (132.11 km/h)
85 mph (136.79 km/h)87.22 mph (140.37 km/h)
90 mph (144.84 km/h)92.35 mph (148.63 km/h)
95 mph (152.89 km/h)97.48 mph (156.89 km/h)
100 mph (160.93 km/h)102.62 mph (165.14 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
18982205237524802593267427632868301331593320344936843942414442734346461349845792
Better Fuel Economy Factory Ratios Increased Power

Most Popular 265/40-R18 Comparisons

To Top