Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
125/90r16 vs 235/40r18 Tire Comparison Side By Side
  125/90-16 235/40-18 Difference
Diameter inches (mm) 24.86 (631.4) 25.4 (645.2) 0.54 (13.8) 2.2%
Width inches (mm) 4.92 (125) 9.25 (235) 4.33 (110) 88%
Circum. inches (mm) 78.09 (1983.6) 79.8 (2026.96) 1.71 (43.35) 2.2%
Sidewall Height inches (mm) 4.43 (112.5) 3.7 (94) -0.73 (-18.5) -16.4%
Revolutions per mile (km) 811.32 (504.13) 793.97 (493.35) -17.35 (-10.78) -2.1%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.44 mph (32.89 km/h)
25 mph (40.23 km/h)25.55 mph (41.11 km/h)
30 mph (48.28 km/h)30.66 mph (49.34 km/h)
35 mph (56.33 km/h)35.76 mph (57.56 km/h)
40 mph (64.37 km/h)40.87 mph (65.78 km/h)
45 mph (72.42 km/h)45.98 mph (74 km/h)
50 mph (80.47 km/h)51.09 mph (82.23 km/h)
55 mph (88.51 km/h)56.2 mph (90.45 km/h)
60 mph (96.56 km/h)61.31 mph (98.67 km/h)
65 mph (104.61 km/h)66.42 mph (106.89 km/h)
70 mph (112.65 km/h)71.53 mph (115.12 km/h)
75 mph (120.7 km/h)76.64 mph (123.34 km/h)
80 mph (128.75 km/h)81.75 mph (131.56 km/h)
85 mph (136.79 km/h)86.86 mph (139.78 km/h)
90 mph (144.84 km/h)91.97 mph (148.01 km/h)
95 mph (152.89 km/h)97.08 mph (156.23 km/h)
100 mph (160.93 km/h)102.19 mph (164.45 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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