| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 235/65-18 | 0.00 % | 50.00 | 1,000.00 | 30.03 | 6.01 | 152.75 |
| 255/60-18 | +0.07 % | 50.03 | 999.34 | 30.05 | 6.02 | 153.00 |
| 305/50-18 | -0.07 % | 49.97 | 1,000.66 | 30.01 | 6.00 | 152.50 |
| 205/75-18 | +0.26 % | 50.13 | 997.38 | 30.11 | 6.05 | 153.75 |
| 275/55-18 | -0.39 % | 49.80 | 1,003.93 | 29.91 | 5.95 | 151.25 |
| 335/45-18 | -0.52 % | 49.74 | 1,005.24 | 29.87 | 5.94 | 150.75 |
| 215/70-18 | -0.59 % | 49.70 | 1,005.90 | 29.85 | 5.93 | 150.50 |
| 195/80-18 | +0.85 % | 50.43 | 991.48 | 30.28 | 6.14 | 156.00 |
| 285/55-18 | +1.05 % | 50.52 | 989.51 | 30.34 | 6.17 | 156.75 |
| 175/85-18 | -1.05 % | 49.48 | 1,010.49 | 29.71 | 5.86 | 148.75 |
| 185/85-18 | +1.18 % | 50.59 | 988.20 | 30.38 | 6.19 | 157.25 |
| 315/50-18 | +1.25 % | 50.62 | 987.54 | 30.40 | 6.20 | 157.50 |
| 225/70-18 | +1.25 % | 50.62 | 987.54 | 30.40 | 6.20 | 157.50 |
| 185/80-18 | -1.25 % | 49.38 | 1,012.46 | 29.65 | 5.83 | 148.00 |
| 295/50-18 | -1.38 % | 49.31 | 1,013.77 | 29.61 | 5.81 | 147.50 |
| 245/60-18 | -1.51 % | 49.25 | 1,015.08 | 29.57 | 5.79 | 147.00 |
| 265/60-18 | +1.64 % | 50.82 | 983.61 | 30.52 | 6.26 | 159.00 |
| 325/45-18 | -1.70 % | 49.15 | 1,017.04 | 29.52 | 5.76 | 146.25 |
| 225/65-18 | -1.70 % | 49.15 | 1,017.04 | 29.52 | 5.76 | 146.25 |
| 245/65-18 | +1.70 % | 50.85 | 982.96 | 30.54 | 6.27 | 159.25 |
| 195/75-18 | -1.70 % | 49.15 | 1,017.04 | 29.52 | 5.76 | 146.25 |
| 265/55-18 | -1.84 % | 49.08 | 1,018.36 | 29.48 | 5.74 | 145.75 |
| Ratio: | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Wheel Size 12
|
|||||||||||||
|
Wheel Size 13
|
|||||||||||||
|
Wheel Size 14
|
|||||||||||||
|
Wheel Size 15
|
|||||||||||||
|
Wheel Size 16
|
|||||||||||||
|
Wheel Size 16.5
|
|||||||||||||
|
Wheel Size 17
|
|||||||||||||
|
Wheel Size 18
|
|||||||||||||
| 145 |
145/25-18
d=20.85
w=1.43
-30.55%
|
145/30-18
d=21.43
w=1.71
-28.65%
|
145/35-18
d=22.00
w=2.00
-26.75%
|
145/40-18
d=22.57
w=2.28
-24.85%
|
145/45-18
d=23.14
w=2.57
-22.94%
|
145/50-18
d=23.71
w=2.85
-21.04%
|
145/55-18
d=24.28
w=3.14
-19.14%
|
145/60-18
d=24.85
w=3.43
-17.24%
|
145/65-18
d=25.42
w=3.71
-15.34%
|
145/70-18
d=25.99
w=4.00
-13.44%
|
145/75-18
d=26.56
w=4.28
-11.54%
|
145/80-18
d=27.13
w=4.57
-9.64%
|
145/85-18
d=27.70
w=4.85
-7.74%
|
| 155 |
155/25-18
d=21.05
w=1.53
-29.89%
|
155/30-18
d=21.66
w=1.83
-27.86%
|
155/35-18
d=22.27
w=2.14
-25.83%
|
155/40-18
d=22.88
w=2.44
-23.80%
|
155/45-18
d=23.49
w=2.75
-21.76%
|
155/50-18
d=24.10
w=3.05
-19.73%
|
155/55-18
d=24.71
w=3.36
-17.70%
|
155/60-18
d=25.32
w=3.66
-15.67%
|
155/65-18
d=25.93
w=3.97
-13.64%
|
155/70-18
d=26.54
w=4.27
-11.60%
|
155/75-18
d=27.15
w=4.58
-9.57%
|
155/80-18
d=27.76
w=4.88
-7.54%
|
155/85-18
d=28.37
w=5.19
-5.51%
|
| 165 |
165/25-18
d=21.25
w=1.62
-29.24%
|
165/30-18
d=21.90
w=1.95
-27.07%
|
165/35-18
d=22.55
w=2.27
-24.91%
|
165/40-18
d=23.20
w=2.60
-22.75%
|
165/45-18
d=23.85
w=2.92
-20.58%
|
165/50-18
d=24.50
w=3.25
-18.42%
|
165/55-18
d=25.15
w=3.57
-16.26%
|
165/60-18
d=25.80
w=3.90
-14.09%
|
165/65-18
d=26.44
w=4.22
-11.93%
|
165/70-18
d=27.09
w=4.55
-9.77%
|
165/75-18
d=27.74
w=4.87
-7.60%
|
165/80-18
d=28.39
w=5.20
-5.44%
|
165/85-18
d=29.04
w=5.52
-3.28%
|
| 175 |
175/25-18
d=21.44
w=1.72
-28.58%
|
175/30-18
d=22.13
w=2.07
-26.29%
|
175/35-18
d=22.82
w=2.41
-23.99%
|
175/40-18
d=23.51
w=2.76
-21.70%
|
175/45-18
d=24.20
w=3.10
-19.40%
|
175/50-18
d=24.89
w=3.44
-17.11%
|
175/55-18
d=25.58
w=3.79
-14.82%
|
175/60-18
d=26.27
w=4.13
-12.52%
|
175/65-18
d=26.96
w=4.48
-10.23%
|
175/70-18
d=27.65
w=4.82
-7.93%
|
175/75-18
d=28.33
w=5.17
-5.64%
|
175/80-18
d=29.02
w=5.51
-3.34%
|
175/85-18
d=29.71
w=5.86
-1.05%
|
| 185 |
185/25-18
d=21.64
w=1.82
-27.93%
|
185/30-18
d=22.37
w=2.19
-25.50%
|
185/35-18
d=23.10
w=2.55
-23.08%
|
185/40-18
d=23.83
w=2.91
-20.65%
|
185/45-18
d=24.56
w=3.28
-18.22%
|
185/50-18
d=25.28
w=3.64
-15.80%
|
185/55-18
d=26.01
w=4.01
-13.37%
|
185/60-18
d=26.74
w=4.37
-10.95%
|
185/65-18
d=27.47
w=4.73
-8.52%
|
185/70-18
d=28.20
w=5.10
-6.10%
|
185/75-18
d=28.93
w=5.46
-3.67%
|
185/80-18
d=29.65
w=5.83
-1.25%
|
185/85-18
d=30.38
w=6.19
+1.18%
|
| 195 |
195/25-18
d=21.84
w=1.92
-27.27%
|
195/30-18
d=22.61
w=2.30
-24.71%
|
195/35-18
d=23.37
w=2.69
-22.16%
|
195/40-18
d=24.14
w=3.07
-19.60%
|
195/45-18
d=24.91
w=3.45
-17.04%
|
195/50-18
d=25.68
w=3.84
-14.49%
|
195/55-18
d=26.44
w=4.22
-11.93%
|
195/60-18
d=27.21
w=4.61
-9.37%
|
195/65-18
d=27.98
w=4.99
-6.82%
|
195/70-18
d=28.75
w=5.37
-4.26%
|
195/75-18
d=29.52
w=5.76
-1.70%
|
195/80-18
d=30.28
w=6.14
+0.85%
|
195/85-18
d=31.05
w=6.53
+3.41%
|
| 205 |
205/25-18
d=22.04
w=2.02
-26.62%
|
205/30-18
d=22.84
w=2.42
-23.93%
|
205/35-18
d=23.65
w=2.82
-21.24%
|
205/40-18
d=24.46
w=3.23
-18.55%
|
205/45-18
d=25.26
w=3.63
-15.86%
|
205/50-18
d=26.07
w=4.04
-13.18%
|
205/55-18
d=26.88
w=4.44
-10.49%
|
205/60-18
d=27.69
w=4.84
-7.80%
|
205/65-18
d=28.49
w=5.25
-5.11%
|
205/70-18
d=29.30
w=5.65
-2.43%
|
205/75-18
d=30.11
w=6.05
+0.26%
|
205/80-18
d=30.91
w=6.46
+2.95%
|
205/85-18
d=31.72
w=6.86
+5.64%
|
| 215 |
215/25-18
d=22.23
w=2.12
-25.96%
|
215/30-18
d=23.08
w=2.54
-23.14%
|
215/35-18
d=23.93
w=2.96
-20.32%
|
215/40-18
d=24.77
w=3.39
-17.50%
|
215/45-18
d=25.62
w=3.81
-14.68%
|
215/50-18
d=26.46
w=4.23
-11.87%
|
215/55-18
d=27.31
w=4.66
-9.05%
|
215/60-18
d=28.16
w=5.08
-6.23%
|
215/65-18
d=29.00
w=5.50
-3.41%
|
215/70-18
d=29.85
w=5.93
-0.59%
|
215/75-18
d=30.70
w=6.35
+2.23%
|
215/80-18
d=31.54
w=6.77
+5.05%
|
215/85-18
d=32.39
w=7.19
+7.87%
|
| 225 |
225/25-18
d=22.43
w=2.21
-25.30%
|
225/30-18
d=23.31
w=2.66
-22.35%
|
225/35-18
d=24.20
w=3.10
-19.40%
|
225/40-18
d=25.09
w=3.54
-16.45%
|
225/45-18
d=25.97
w=3.99
-13.50%
|
225/50-18
d=26.86
w=4.43
-10.55%
|
225/55-18
d=27.74
w=4.87
-7.60%
|
225/60-18
d=28.63
w=5.31
-4.65%
|
225/65-18
d=29.52
w=5.76
-1.70%
|
225/70-18
d=30.40
w=6.20
+1.25%
|
225/75-18
d=31.29
w=6.64
+4.20%
|
225/80-18
d=32.17
w=7.09
+7.15%
|
225/85-18
d=33.06
w=7.53
+10.10%
|
| 235 |
235/25-18
d=22.63
w=2.31
-24.65%
|
235/30-18
d=23.55
w=2.78
-21.57%
|
235/35-18
d=24.48
w=3.24
-18.49%
|
235/40-18
d=25.40
w=3.70
-15.41%
|
235/45-18
d=26.33
w=4.16
-12.32%
|
235/50-18
d=27.25
w=4.63
-9.24%
|
235/55-18
d=28.18
w=5.09
-6.16%
|
235/60-18
d=29.10
w=5.55
-3.08%
|
235/65-18
d=30.03
w=6.01
0.00%
|
235/70-18
d=30.95
w=6.48
+3.08%
|
235/75-18
d=31.88
w=6.94
+6.16%
|
235/80-18
d=32.80
w=7.40
+9.24%
|
235/85-18
d=33.73
w=7.86
+12.32%
|
| 245 |
245/25-18
d=22.82
w=2.41
-23.99%
|
245/30-18
d=23.79
w=2.89
-20.78%
|
245/35-18
d=24.75
w=3.38
-17.57%
|
245/40-18
d=25.72
w=3.86
-14.36%
|
245/45-18
d=26.68
w=4.34
-11.14%
|
245/50-18
d=27.65
w=4.82
-7.93%
|
245/55-18
d=28.61
w=5.31
-4.72%
|
245/60-18
d=29.57
w=5.79
-1.51%
|
245/65-18
d=30.54
w=6.27
+1.70%
|
245/70-18
d=31.50
w=6.75
+4.92%
|
245/75-18
d=32.47
w=7.23
+8.13%
|
245/80-18
d=33.43
w=7.72
+11.34%
|
245/85-18
d=34.40
w=8.20
+14.55%
|
| 255 |
255/25-18
d=23.02
w=2.51
-23.34%
|
255/30-18
d=24.02
w=3.01
-19.99%
|
255/35-18
d=25.03
w=3.51
-16.65%
|
255/40-18
d=26.03
w=4.02
-13.31%
|
255/45-18
d=27.04
w=4.52
-9.96%
|
255/50-18
d=28.04
w=5.02
-6.62%
|
255/55-18
d=29.04
w=5.52
-3.28%
|
255/60-18
d=30.05
w=6.02
+0.07%
|
255/65-18
d=31.05
w=6.53
+3.41%
|
255/70-18
d=32.06
w=7.03
+6.75%
|
255/75-18
d=33.06
w=7.53
+10.10%
|
255/80-18
d=34.06
w=8.03
+13.44%
|
255/85-18
d=35.07
w=8.53
+16.78%
|
| 265 |
265/25-18
d=23.22
w=2.61
-22.68%
|
265/30-18
d=24.26
w=3.13
-19.21%
|
265/35-18
d=25.30
w=3.65
-15.73%
|
265/40-18
d=26.35
w=4.17
-12.26%
|
265/45-18
d=27.39
w=4.69
-8.78%
|
265/50-18
d=28.43
w=5.22
-5.31%
|
265/55-18
d=29.48
w=5.74
-1.84%
|
265/60-18
d=30.52
w=6.26
+1.64%
|
265/65-18
d=31.56
w=6.78
+5.11%
|
265/70-18
d=32.61
w=7.30
+8.59%
|
265/75-18
d=33.65
w=7.82
+12.06%
|
265/80-18
d=34.69
w=8.35
+15.54%
|
265/85-18
d=35.74
w=8.87
+19.01%
|
| 275 |
275/25-18
d=23.41
w=2.71
-22.03%
|
275/30-18
d=24.50
w=3.25
-18.42%
|
275/35-18
d=25.58
w=3.79
-14.82%
|
275/40-18
d=26.66
w=4.33
-11.21%
|
275/45-18
d=27.74
w=4.87
-7.60%
|
275/50-18
d=28.83
w=5.41
-4.00%
|
275/55-18
d=29.91
w=5.95
-0.39%
|
275/60-18
d=30.99
w=6.50
+3.21%
|
275/65-18
d=32.07
w=7.04
+6.82%
|
275/70-18
d=33.16
w=7.58
+10.42%
|
275/75-18
d=34.24
w=8.12
+14.03%
|
275/80-18
d=35.32
w=8.66
+17.63%
|
275/85-18
d=36.41
w=9.20
+21.24%
|
| 285 |
285/25-18
d=23.61
w=2.81
-21.37%
|
285/30-18
d=24.73
w=3.37
-17.63%
|
285/35-18
d=25.85
w=3.93
-13.90%
|
285/40-18
d=26.98
w=4.49
-10.16%
|
285/45-18
d=28.10
w=5.05
-6.42%
|
285/50-18
d=29.22
w=5.61
-2.69%
|
285/55-18
d=30.34
w=6.17
+1.05%
|
285/60-18
d=31.46
w=6.73
+4.79%
|
285/65-18
d=32.59
w=7.29
+8.52%
|
285/70-18
d=33.71
w=7.85
+12.26%
|
285/75-18
d=34.83
w=8.42
+16.00%
|
285/80-18
d=35.95
w=8.98
+19.73%
|
285/85-18
d=37.07
w=9.54
+23.47%
|
| 295 |
295/25-18
d=23.81
w=2.90
-20.72%
|
295/30-18
d=24.97
w=3.48
-16.85%
|
295/35-18
d=26.13
w=4.06
-12.98%
|
295/40-18
d=27.29
w=4.65
-9.11%
|
295/45-18
d=28.45
w=5.23
-5.24%
|
295/50-18
d=29.61
w=5.81
-1.38%
|
295/55-18
d=30.78
w=6.39
+2.49%
|
295/60-18
d=31.94
w=6.97
+6.36%
|
295/65-18
d=33.10
w=7.55
+10.23%
|
295/70-18
d=34.26
w=8.13
+14.09%
|
295/75-18
d=35.42
w=8.71
+17.96%
|
295/80-18
d=36.58
w=9.29
+21.83%
|
295/85-18
d=37.74
w=9.87
+25.70%
|
| 305 |
305/25-18
d=24.00
w=3.00
-20.06%
|
305/30-18
d=25.20
w=3.60
-16.06%
|
305/35-18
d=26.41
w=4.20
-12.06%
|
305/40-18
d=27.61
w=4.80
-8.06%
|
305/45-18
d=28.81
w=5.40
-4.06%
|
305/50-18
d=30.01
w=6.00
-0.07%
|
305/55-18
d=31.21
w=6.60
+3.93%
|
305/60-18
d=32.41
w=7.20
+7.93%
|
305/65-18
d=33.61
w=7.81
+11.93%
|
305/70-18
d=34.81
w=8.41
+15.93%
|
305/75-18
d=36.01
w=9.01
+19.93%
|
305/80-18
d=37.21
w=9.61
+23.93%
|
305/85-18
d=38.41
w=10.21
+27.93%
|
| 315 |
315/25-18
d=24.20
w=3.10
-19.40%
|
315/30-18
d=25.44
w=3.72
-15.27%
|
315/35-18
d=26.68
w=4.34
-11.14%
|
315/40-18
d=27.92
w=4.96
-7.01%
|
315/45-18
d=29.16
w=5.58
-2.88%
|
315/50-18
d=30.40
w=6.20
+1.25%
|
315/55-18
d=31.64
w=6.82
+5.38%
|
315/60-18
d=32.88
w=7.44
+9.51%
|
315/65-18
d=34.12
w=8.06
+13.64%
|
315/70-18
d=35.36
w=8.68
+17.77%
|
315/75-18
d=36.60
w=9.30
+21.90%
|
315/80-18
d=37.84
w=9.92
+26.03%
|
315/85-18
d=39.08
w=10.54
+30.16%
|
| 325 |
325/25-18
d=24.40
w=3.20
-18.75%
|
325/30-18
d=25.68
w=3.84
-14.49%
|
325/35-18
d=26.96
w=4.48
-10.23%
|
325/40-18
d=28.24
w=5.12
-5.97%
|
325/45-18
d=29.52
w=5.76
-1.70%
|
325/50-18
d=30.80
w=6.40
+2.56%
|
325/55-18
d=32.07
w=7.04
+6.82%
|
325/60-18
d=33.35
w=7.68
+11.08%
|
325/65-18
d=34.63
w=8.32
+15.34%
|
325/70-18
d=35.91
w=8.96
+19.60%
|
325/75-18
d=37.19
w=9.60
+23.86%
|
325/80-18
d=38.47
w=10.24
+28.12%
|
325/85-18
d=39.75
w=10.88
+32.38%
|
| 335 |
335/25-18
d=24.59
w=3.30
-18.09%
|
335/30-18
d=25.91
w=3.96
-13.70%
|
335/35-18
d=27.23
w=4.62
-9.31%
|
335/40-18
d=28.55
w=5.28
-4.92%
|
335/45-18
d=29.87
w=5.94
-0.52%
|
335/50-18
d=31.19
w=6.59
+3.87%
|
335/55-18
d=32.51
w=7.25
+8.26%
|
335/60-18
d=33.83
w=7.91
+12.65%
|
335/65-18
d=35.15
w=8.57
+17.04%
|
335/70-18
d=36.46
w=9.23
+21.44%
|
335/75-18
d=37.78
w=9.89
+25.83%
|
335/80-18
d=39.10
w=10.55
+30.22%
|
335/85-18
d=40.42
w=11.21
+34.61%
|
|
Wheel Size 19
|
|||||||||||||
|
Wheel Size 20
|
|||||||||||||
|
Wheel Size 21
|
|||||||||||||
The information on this page is intended to be helpful, but there is absolutely no guarantee of its accuracy, safety, or applicability for any particular use. The data is calculated mathematically, not taken from any official or recommended guide.
Please excercise a common sense, follow manufacturer and dealer recommendations, and check with other sources.
Tires are a safety equipment, don't take their selection lightly!