Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
215/50r18 vs 215/55r18 Tire Comparison Side By Side
  215/50-18 215/55-18 Difference
Diameter inches (mm) 26.46 (672.2) 27.31 (693.7) 0.85 (21.5) 3.2%
Width inches (mm) 8.46 (215) 8.46 (215) 0 (0) 0%
Circum. inches (mm) 83.14 (2111.78) 85.8 (2179.32) 2.66 (67.54) 3.2%
Sidewall Height inches (mm) 4.23 (107.5) 4.66 (118.25) 0.42 (10.75) 10%
Revolutions per mile (km) 762.08 (473.53) 738.46 (458.86) -23.62 (-14.68) -3.1%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.64 mph (33.22 km/h)
25 mph (40.23 km/h)25.8 mph (41.52 km/h)
30 mph (48.28 km/h)30.96 mph (49.82 km/h)
35 mph (56.33 km/h)36.12 mph (58.13 km/h)
40 mph (64.37 km/h)41.28 mph (66.43 km/h)
45 mph (72.42 km/h)46.44 mph (74.74 km/h)
50 mph (80.47 km/h)51.6 mph (83.04 km/h)
55 mph (88.51 km/h)56.76 mph (91.35 km/h)
60 mph (96.56 km/h)61.92 mph (99.65 km/h)
65 mph (104.61 km/h)67.08 mph (107.95 km/h)
70 mph (112.65 km/h)72.24 mph (116.26 km/h)
75 mph (120.7 km/h)77.4 mph (124.56 km/h)
80 mph (128.75 km/h)82.56 mph (132.87 km/h)
85 mph (136.79 km/h)87.72 mph (141.17 km/h)
90 mph (144.84 km/h)92.88 mph (149.47 km/h)
95 mph (152.89 km/h)98.04 mph (157.78 km/h)
100 mph (160.93 km/h)103.2 mph (166.08 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
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