Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
26/12r12 vs 30/10r14 Tire Comparison Side By Side
  26/12-12 30/10-14 Difference
Diameter inches (mm) 25.93 (658.6) 30 (762) 4.07 (103.4) 15.7%
Width inches (mm) 12.01 (305) 10 (254) -2.01 (-51) -16.7%
Circum. inches (mm) 81.46 (2069.05) 94.25 (2393.89) 12.79 (324.84) 15.7%
Sidewall Height inches (mm) 6.96 (176.9) 8 (203.2) 1.04 (26.3) 14.9%
Revolutions per mile (km) 777.82 (483.31) 672.27 (417.73) -105.55 (-65.58) -13.6%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)23.14 mph (37.24 km/h)
25 mph (40.23 km/h)28.92 mph (46.55 km/h)
30 mph (48.28 km/h)34.71 mph (55.86 km/h)
35 mph (56.33 km/h)40.49 mph (65.17 km/h)
40 mph (64.37 km/h)46.28 mph (74.48 km/h)
45 mph (72.42 km/h)52.06 mph (83.79 km/h)
50 mph (80.47 km/h)57.85 mph (93.1 km/h)
55 mph (88.51 km/h)63.63 mph (102.41 km/h)
60 mph (96.56 km/h)69.42 mph (111.72 km/h)
65 mph (104.61 km/h)75.2 mph (121.03 km/h)
70 mph (112.65 km/h)80.99 mph (130.34 km/h)
75 mph (120.7 km/h)86.77 mph (139.65 km/h)
80 mph (128.75 km/h)92.56 mph (148.96 km/h)
85 mph (136.79 km/h)98.34 mph (158.27 km/h)
90 mph (144.84 km/h)104.13 mph (167.58 km/h)
95 mph (152.89 km/h)109.91 mph (176.89 km/h)
100 mph (160.93 km/h)115.7 mph (186.2 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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