Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
145/60r15 vs 175/55r15 Tire Comparison Side By Side
  145/60-15 175/55-15 Difference
Diameter inches (mm) 21.85 (555) 22.58 (573.5) 0.73 (18.5) 3.3%
Width inches (mm) 5.71 (145) 6.89 (175) 1.18 (30) 20.7%
Circum. inches (mm) 68.65 (1743.58) 70.93 (1801.7) 2.29 (58.12) 3.3%
Sidewall Height inches (mm) 3.43 (87) 3.79 (96.25) 0.36 (9.25) 10.6%
Revolutions per mile (km) 923.01 (573.53) 893.23 (555.03) -29.77 (-18.5) -3.2%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.67 mph (33.26 km/h)
25 mph (40.23 km/h)25.83 mph (41.57 km/h)
30 mph (48.28 km/h)31 mph (49.89 km/h)
35 mph (56.33 km/h)36.17 mph (58.2 km/h)
40 mph (64.37 km/h)41.33 mph (66.52 km/h)
45 mph (72.42 km/h)46.5 mph (74.83 km/h)
50 mph (80.47 km/h)51.67 mph (83.15 km/h)
55 mph (88.51 km/h)56.83 mph (91.46 km/h)
60 mph (96.56 km/h)62 mph (99.78 km/h)
65 mph (104.61 km/h)67.17 mph (108.09 km/h)
70 mph (112.65 km/h)72.33 mph (116.41 km/h)
75 mph (120.7 km/h)77.5 mph (124.72 km/h)
80 mph (128.75 km/h)82.67 mph (133.04 km/h)
85 mph (136.79 km/h)87.83 mph (141.35 km/h)
90 mph (144.84 km/h)93 mph (149.67 km/h)
95 mph (152.89 km/h)98.17 mph (157.98 km/h)
100 mph (160.93 km/h)103.33 mph (166.3 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
22732641284429703105320233083434360837823976413044114720496251175204552359686935
Better Fuel Economy Factory Ratios Increased Power

Most Popular 145/60-R15 Comparisons

To Top