Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
245/45r18 vs 235/45r18 Tire Comparison Side By Side
  245/45-18 235/45-18 Difference
Diameter inches (mm) 26.68 (677.7) 26.33 (668.7) -0.35 (-9) -1.3%
Width inches (mm) 9.65 (245) 9.25 (235) -0.39 (-10) -4.1%
Circum. inches (mm) 83.82 (2129.06) 82.71 (2100.78) -1.11 (-28.27) -1.3%
Sidewall Height inches (mm) 4.34 (110.25) 4.16 (105.75) -0.18 (-4.5) -4.1%
Revolutions per mile (km) 755.9 (469.69) 766.07 (476.01) 10.17 (6.32) 1.3%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.73 mph (31.76 km/h)
25 mph (40.23 km/h)24.67 mph (39.7 km/h)
30 mph (48.28 km/h)29.6 mph (47.64 km/h)
35 mph (56.33 km/h)34.54 mph (55.58 km/h)
40 mph (64.37 km/h)39.47 mph (63.52 km/h)
45 mph (72.42 km/h)44.4 mph (71.46 km/h)
50 mph (80.47 km/h)49.34 mph (79.4 km/h)
55 mph (88.51 km/h)54.27 mph (87.34 km/h)
60 mph (96.56 km/h)59.2 mph (95.28 km/h)
65 mph (104.61 km/h)64.14 mph (103.22 km/h)
70 mph (112.65 km/h)69.07 mph (111.16 km/h)
75 mph (120.7 km/h)74 mph (119.1 km/h)
80 mph (128.75 km/h)78.94 mph (127.04 km/h)
85 mph (136.79 km/h)83.87 mph (134.98 km/h)
90 mph (144.84 km/h)88.8 mph (142.92 km/h)
95 mph (152.89 km/h)93.74 mph (150.86 km/h)
100 mph (160.93 km/h)98.67 mph (158.8 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
19492265243925472663274628372945309432443410354237834048425643884463473751185948
Better Fuel Economy Factory Ratios Increased Power

Most Popular 245/45-R18 Comparisons

To Top