Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
355/25r21 vs 265/70r17 Tire Comparison Side By Side
  355/25-21 265/70-17 Difference
Diameter inches (mm) 27.99 (710.9) 31.61 (802.8) 3.62 (91.9) 12.9%
Width inches (mm) 13.98 (355) 10.43 (265) -3.54 (-90) -25.4%
Circum. inches (mm) 87.93 (2233.36) 99.29 (2522.07) 11.37 (288.71) 12.9%
Sidewall Height inches (mm) 3.49 (88.75) 7.3 (185.5) 3.81 (96.75) 109%
Revolutions per mile (km) 720.59 (447.76) 638.1 (396.5) -82.49 (-51.26) -11.4%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)22.59 mph (36.35 km/h)
25 mph (40.23 km/h)28.23 mph (45.43 km/h)
30 mph (48.28 km/h)33.88 mph (54.52 km/h)
35 mph (56.33 km/h)39.52 mph (63.61 km/h)
40 mph (64.37 km/h)45.17 mph (72.7 km/h)
45 mph (72.42 km/h)50.82 mph (81.78 km/h)
50 mph (80.47 km/h)56.46 mph (90.87 km/h)
55 mph (88.51 km/h)62.11 mph (99.96 km/h)
60 mph (96.56 km/h)67.76 mph (109.04 km/h)
65 mph (104.61 km/h)73.4 mph (118.13 km/h)
70 mph (112.65 km/h)79.05 mph (127.22 km/h)
75 mph (120.7 km/h)84.7 mph (136.3 km/h)
80 mph (128.75 km/h)90.34 mph (145.39 km/h)
85 mph (136.79 km/h)95.99 mph (154.48 km/h)
90 mph (144.84 km/h)101.63 mph (163.57 km/h)
95 mph (152.89 km/h)107.28 mph (172.65 km/h)
100 mph (160.93 km/h)112.93 mph (181.74 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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