| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 285/60-18 | 0.00 % | 50.00 | 1,000.00 | 31.46 | 6.73 | 171.00 |
| 245/70-18 | +0.13 % | 50.06 | 998.75 | 31.50 | 6.75 | 171.50 |
| 215/80-18 | +0.25 % | 50.13 | 997.50 | 31.54 | 6.77 | 172.00 |
| 265/65-18 | +0.31 % | 50.16 | 996.87 | 31.56 | 6.78 | 172.25 |
| 315/55-18 | +0.56 % | 50.28 | 994.37 | 31.64 | 6.82 | 173.25 |
| 225/75-18 | -0.56 % | 49.72 | 1,005.63 | 31.29 | 6.64 | 168.75 |
| 305/55-18 | -0.81 % | 49.59 | 1,008.13 | 31.21 | 6.60 | 167.75 |
| 205/85-18 | +0.81 % | 50.41 | 991.87 | 31.72 | 6.86 | 174.25 |
| 335/50-18 | -0.88 % | 49.56 | 1,008.76 | 31.19 | 6.59 | 167.50 |
| 255/65-18 | -1.31 % | 49.34 | 1,013.14 | 31.05 | 6.53 | 165.75 |
| 235/75-18 | +1.31 % | 50.66 | 986.86 | 31.88 | 6.94 | 176.25 |
| 195/85-18 | -1.31 % | 49.34 | 1,013.14 | 31.05 | 6.53 | 165.75 |
| 275/60-18 | -1.50 % | 49.25 | 1,015.02 | 30.99 | 6.50 | 165.00 |
| 295/60-18 | +1.50 % | 50.75 | 984.98 | 31.94 | 6.97 | 177.00 |
| 235/70-18 | -1.63 % | 49.19 | 1,016.27 | 30.95 | 6.48 | 164.50 |
| 205/80-18 | -1.75 % | 49.12 | 1,017.52 | 30.91 | 6.46 | 164.00 |
| 255/70-18 | +1.88 % | 50.94 | 981.23 | 32.06 | 7.03 | 178.50 |
| 325/55-18 | +1.94 % | 50.97 | 980.61 | 32.07 | 7.04 | 178.75 |
| 275/65-18 | +1.94 % | 50.97 | 980.61 | 32.07 | 7.04 | 178.75 |
| 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
-33.72%
|
145/30-18
d=21.43
w=1.71
-31.91%
|
145/35-18
d=22.00
w=2.00
-30.09%
|
145/40-18
d=22.57
w=2.28
-28.28%
|
145/45-18
d=23.14
w=2.57
-26.46%
|
145/50-18
d=23.71
w=2.85
-24.65%
|
145/55-18
d=24.28
w=3.14
-22.84%
|
145/60-18
d=24.85
w=3.43
-21.02%
|
145/65-18
d=25.42
w=3.71
-19.21%
|
145/70-18
d=25.99
w=4.00
-17.39%
|
145/75-18
d=26.56
w=4.28
-15.58%
|
145/80-18
d=27.13
w=4.57
-13.76%
|
145/85-18
d=27.70
w=4.85
-11.95%
|
| 155 |
155/25-18
d=21.05
w=1.53
-33.10%
|
155/30-18
d=21.66
w=1.83
-31.16%
|
155/35-18
d=22.27
w=2.14
-29.22%
|
155/40-18
d=22.88
w=2.44
-27.28%
|
155/45-18
d=23.49
w=2.75
-25.34%
|
155/50-18
d=24.10
w=3.05
-23.40%
|
155/55-18
d=24.71
w=3.36
-21.46%
|
155/60-18
d=25.32
w=3.66
-19.52%
|
155/65-18
d=25.93
w=3.97
-17.58%
|
155/70-18
d=26.54
w=4.27
-15.64%
|
155/75-18
d=27.15
w=4.58
-13.70%
|
155/80-18
d=27.76
w=4.88
-11.76%
|
155/85-18
d=28.37
w=5.19
-9.82%
|
| 165 |
165/25-18
d=21.25
w=1.62
-32.47%
|
165/30-18
d=21.90
w=1.95
-30.41%
|
165/35-18
d=22.55
w=2.27
-28.34%
|
165/40-18
d=23.20
w=2.60
-26.28%
|
165/45-18
d=23.85
w=2.92
-24.21%
|
165/50-18
d=24.50
w=3.25
-22.15%
|
165/55-18
d=25.15
w=3.57
-20.08%
|
165/60-18
d=25.80
w=3.90
-18.02%
|
165/65-18
d=26.44
w=4.22
-15.95%
|
165/70-18
d=27.09
w=4.55
-13.89%
|
165/75-18
d=27.74
w=4.87
-11.82%
|
165/80-18
d=28.39
w=5.20
-9.76%
|
165/85-18
d=29.04
w=5.52
-7.70%
|
| 175 |
175/25-18
d=21.44
w=1.72
-31.84%
|
175/30-18
d=22.13
w=2.07
-29.65%
|
175/35-18
d=22.82
w=2.41
-27.46%
|
175/40-18
d=23.51
w=2.76
-25.28%
|
175/45-18
d=24.20
w=3.10
-23.09%
|
175/50-18
d=24.89
w=3.44
-20.90%
|
175/55-18
d=25.58
w=3.79
-18.71%
|
175/60-18
d=26.27
w=4.13
-16.52%
|
175/65-18
d=26.96
w=4.48
-14.33%
|
175/70-18
d=27.65
w=4.82
-12.14%
|
175/75-18
d=28.33
w=5.17
-9.95%
|
175/80-18
d=29.02
w=5.51
-7.76%
|
175/85-18
d=29.71
w=5.86
-5.57%
|
| 185 |
185/25-18
d=21.64
w=1.82
-31.22%
|
185/30-18
d=22.37
w=2.19
-28.90%
|
185/35-18
d=23.10
w=2.55
-26.59%
|
185/40-18
d=23.83
w=2.91
-24.27%
|
185/45-18
d=24.56
w=3.28
-21.96%
|
185/50-18
d=25.28
w=3.64
-19.64%
|
185/55-18
d=26.01
w=4.01
-17.33%
|
185/60-18
d=26.74
w=4.37
-15.02%
|
185/65-18
d=27.47
w=4.73
-12.70%
|
185/70-18
d=28.20
w=5.10
-10.39%
|
185/75-18
d=28.93
w=5.46
-8.07%
|
185/80-18
d=29.65
w=5.83
-5.76%
|
185/85-18
d=30.38
w=6.19
-3.44%
|
| 195 |
195/25-18
d=21.84
w=1.92
-30.59%
|
195/30-18
d=22.61
w=2.30
-28.15%
|
195/35-18
d=23.37
w=2.69
-25.71%
|
195/40-18
d=24.14
w=3.07
-23.27%
|
195/45-18
d=24.91
w=3.45
-20.83%
|
195/50-18
d=25.68
w=3.84
-18.39%
|
195/55-18
d=26.44
w=4.22
-15.95%
|
195/60-18
d=27.21
w=4.61
-13.51%
|
195/65-18
d=27.98
w=4.99
-11.07%
|
195/70-18
d=28.75
w=5.37
-8.63%
|
195/75-18
d=29.52
w=5.76
-6.19%
|
195/80-18
d=30.28
w=6.14
-3.75%
|
195/85-18
d=31.05
w=6.53
-1.31%
|
| 205 |
205/25-18
d=22.04
w=2.02
-29.97%
|
205/30-18
d=22.84
w=2.42
-27.40%
|
205/35-18
d=23.65
w=2.82
-24.84%
|
205/40-18
d=24.46
w=3.23
-22.27%
|
205/45-18
d=25.26
w=3.63
-19.71%
|
205/50-18
d=26.07
w=4.04
-17.14%
|
205/55-18
d=26.88
w=4.44
-14.58%
|
205/60-18
d=27.69
w=4.84
-12.01%
|
205/65-18
d=28.49
w=5.25
-9.45%
|
205/70-18
d=29.30
w=5.65
-6.88%
|
205/75-18
d=30.11
w=6.05
-4.32%
|
205/80-18
d=30.91
w=6.46
-1.75%
|
205/85-18
d=31.72
w=6.86
+0.81%
|
| 215 |
215/25-18
d=22.23
w=2.12
-29.34%
|
215/30-18
d=23.08
w=2.54
-26.65%
|
215/35-18
d=23.93
w=2.96
-23.96%
|
215/40-18
d=24.77
w=3.39
-21.27%
|
215/45-18
d=25.62
w=3.81
-18.58%
|
215/50-18
d=26.46
w=4.23
-15.89%
|
215/55-18
d=27.31
w=4.66
-13.20%
|
215/60-18
d=28.16
w=5.08
-10.51%
|
215/65-18
d=29.00
w=5.50
-7.82%
|
215/70-18
d=29.85
w=5.93
-5.13%
|
215/75-18
d=30.70
w=6.35
-2.44%
|
215/80-18
d=31.54
w=6.77
+0.25%
|
215/85-18
d=32.39
w=7.19
+2.94%
|
| 225 |
225/25-18
d=22.43
w=2.21
-28.72%
|
225/30-18
d=23.31
w=2.66
-25.90%
|
225/35-18
d=24.20
w=3.10
-23.09%
|
225/40-18
d=25.09
w=3.54
-20.27%
|
225/45-18
d=25.97
w=3.99
-17.45%
|
225/50-18
d=26.86
w=4.43
-14.64%
|
225/55-18
d=27.74
w=4.87
-11.82%
|
225/60-18
d=28.63
w=5.31
-9.01%
|
225/65-18
d=29.52
w=5.76
-6.19%
|
225/70-18
d=30.40
w=6.20
-3.38%
|
225/75-18
d=31.29
w=6.64
-0.56%
|
225/80-18
d=32.17
w=7.09
+2.25%
|
225/85-18
d=33.06
w=7.53
+5.07%
|
| 235 |
235/25-18
d=22.63
w=2.31
-28.09%
|
235/30-18
d=23.55
w=2.78
-25.15%
|
235/35-18
d=24.48
w=3.24
-22.21%
|
235/40-18
d=25.40
w=3.70
-19.27%
|
235/45-18
d=26.33
w=4.16
-16.33%
|
235/50-18
d=27.25
w=4.63
-13.39%
|
235/55-18
d=28.18
w=5.09
-10.45%
|
235/60-18
d=29.10
w=5.55
-7.51%
|
235/65-18
d=30.03
w=6.01
-4.57%
|
235/70-18
d=30.95
w=6.48
-1.63%
|
235/75-18
d=31.88
w=6.94
+1.31%
|
235/80-18
d=32.80
w=7.40
+4.25%
|
235/85-18
d=33.73
w=7.86
+7.19%
|
| 245 |
245/25-18
d=22.82
w=2.41
-27.46%
|
245/30-18
d=23.79
w=2.89
-24.40%
|
245/35-18
d=24.75
w=3.38
-21.33%
|
245/40-18
d=25.72
w=3.86
-18.27%
|
245/45-18
d=26.68
w=4.34
-15.20%
|
245/50-18
d=27.65
w=4.82
-12.14%
|
245/55-18
d=28.61
w=5.31
-9.07%
|
245/60-18
d=29.57
w=5.79
-6.01%
|
245/65-18
d=30.54
w=6.27
-2.94%
|
245/70-18
d=31.50
w=6.75
+0.13%
|
245/75-18
d=32.47
w=7.23
+3.19%
|
245/80-18
d=33.43
w=7.72
+6.26%
|
245/85-18
d=34.40
w=8.20
+9.32%
|
| 255 |
255/25-18
d=23.02
w=2.51
-26.84%
|
255/30-18
d=24.02
w=3.01
-23.65%
|
255/35-18
d=25.03
w=3.51
-20.46%
|
255/40-18
d=26.03
w=4.02
-17.27%
|
255/45-18
d=27.04
w=4.52
-14.08%
|
255/50-18
d=28.04
w=5.02
-10.89%
|
255/55-18
d=29.04
w=5.52
-7.70%
|
255/60-18
d=30.05
w=6.02
-4.50%
|
255/65-18
d=31.05
w=6.53
-1.31%
|
255/70-18
d=32.06
w=7.03
+1.88%
|
255/75-18
d=33.06
w=7.53
+5.07%
|
255/80-18
d=34.06
w=8.03
+8.26%
|
255/85-18
d=35.07
w=8.53
+11.45%
|
| 265 |
265/25-18
d=23.22
w=2.61
-26.21%
|
265/30-18
d=24.26
w=3.13
-22.90%
|
265/35-18
d=25.30
w=3.65
-19.58%
|
265/40-18
d=26.35
w=4.17
-16.27%
|
265/45-18
d=27.39
w=4.69
-12.95%
|
265/50-18
d=28.43
w=5.22
-9.63%
|
265/55-18
d=29.48
w=5.74
-6.32%
|
265/60-18
d=30.52
w=6.26
-3.00%
|
265/65-18
d=31.56
w=6.78
+0.31%
|
265/70-18
d=32.61
w=7.30
+3.63%
|
265/75-18
d=33.65
w=7.82
+6.94%
|
265/80-18
d=34.69
w=8.35
+10.26%
|
265/85-18
d=35.74
w=8.87
+13.58%
|
| 275 |
275/25-18
d=23.41
w=2.71
-25.59%
|
275/30-18
d=24.50
w=3.25
-22.15%
|
275/35-18
d=25.58
w=3.79
-18.71%
|
275/40-18
d=26.66
w=4.33
-15.27%
|
275/45-18
d=27.74
w=4.87
-11.82%
|
275/50-18
d=28.83
w=5.41
-8.38%
|
275/55-18
d=29.91
w=5.95
-4.94%
|
275/60-18
d=30.99
w=6.50
-1.50%
|
275/65-18
d=32.07
w=7.04
+1.94%
|
275/70-18
d=33.16
w=7.58
+5.38%
|
275/75-18
d=34.24
w=8.12
+8.82%
|
275/80-18
d=35.32
w=8.66
+12.26%
|
275/85-18
d=36.41
w=9.20
+15.70%
|
| 285 |
285/25-18
d=23.61
w=2.81
-24.96%
|
285/30-18
d=24.73
w=3.37
-21.40%
|
285/35-18
d=25.85
w=3.93
-17.83%
|
285/40-18
d=26.98
w=4.49
-14.26%
|
285/45-18
d=28.10
w=5.05
-10.70%
|
285/50-18
d=29.22
w=5.61
-7.13%
|
285/55-18
d=30.34
w=6.17
-3.57%
|
285/60-18
d=31.46
w=6.73
0.00%
|
285/65-18
d=32.59
w=7.29
+3.57%
|
285/70-18
d=33.71
w=7.85
+7.13%
|
285/75-18
d=34.83
w=8.42
+10.70%
|
285/80-18
d=35.95
w=8.98
+14.26%
|
285/85-18
d=37.07
w=9.54
+17.83%
|
| 295 |
295/25-18
d=23.81
w=2.90
-24.34%
|
295/30-18
d=24.97
w=3.48
-20.65%
|
295/35-18
d=26.13
w=4.06
-16.95%
|
295/40-18
d=27.29
w=4.65
-13.26%
|
295/45-18
d=28.45
w=5.23
-9.57%
|
295/50-18
d=29.61
w=5.81
-5.88%
|
295/55-18
d=30.78
w=6.39
-2.19%
|
295/60-18
d=31.94
w=6.97
+1.50%
|
295/65-18
d=33.10
w=7.55
+5.19%
|
295/70-18
d=34.26
w=8.13
+8.88%
|
295/75-18
d=35.42
w=8.71
+12.58%
|
295/80-18
d=36.58
w=9.29
+16.27%
|
295/85-18
d=37.74
w=9.87
+19.96%
|
| 305 |
305/25-18
d=24.00
w=3.00
-23.71%
|
305/30-18
d=25.20
w=3.60
-19.89%
|
305/35-18
d=26.41
w=4.20
-16.08%
|
305/40-18
d=27.61
w=4.80
-12.26%
|
305/45-18
d=28.81
w=5.40
-8.45%
|
305/50-18
d=30.01
w=6.00
-4.63%
|
305/55-18
d=31.21
w=6.60
-0.81%
|
305/60-18
d=32.41
w=7.20
+3.00%
|
305/65-18
d=33.61
w=7.81
+6.82%
|
305/70-18
d=34.81
w=8.41
+10.64%
|
305/75-18
d=36.01
w=9.01
+14.45%
|
305/80-18
d=37.21
w=9.61
+18.27%
|
305/85-18
d=38.41
w=10.21
+22.08%
|
| 315 |
315/25-18
d=24.20
w=3.10
-23.09%
|
315/30-18
d=25.44
w=3.72
-19.14%
|
315/35-18
d=26.68
w=4.34
-15.20%
|
315/40-18
d=27.92
w=4.96
-11.26%
|
315/45-18
d=29.16
w=5.58
-7.32%
|
315/50-18
d=30.40
w=6.20
-3.38%
|
315/55-18
d=31.64
w=6.82
+0.56%
|
315/60-18
d=32.88
w=7.44
+4.50%
|
315/65-18
d=34.12
w=8.06
+8.45%
|
315/70-18
d=35.36
w=8.68
+12.39%
|
315/75-18
d=36.60
w=9.30
+16.33%
|
315/80-18
d=37.84
w=9.92
+20.27%
|
315/85-18
d=39.08
w=10.54
+24.21%
|
| 325 |
325/25-18
d=24.40
w=3.20
-22.46%
|
325/30-18
d=25.68
w=3.84
-18.39%
|
325/35-18
d=26.96
w=4.48
-14.33%
|
325/40-18
d=28.24
w=5.12
-10.26%
|
325/45-18
d=29.52
w=5.76
-6.19%
|
325/50-18
d=30.80
w=6.40
-2.13%
|
325/55-18
d=32.07
w=7.04
+1.94%
|
325/60-18
d=33.35
w=7.68
+6.01%
|
325/65-18
d=34.63
w=8.32
+10.07%
|
325/70-18
d=35.91
w=8.96
+14.14%
|
325/75-18
d=37.19
w=9.60
+18.21%
|
325/80-18
d=38.47
w=10.24
+22.27%
|
325/85-18
d=39.75
w=10.88
+26.34%
|
| 335 |
335/25-18
d=24.59
w=3.30
-21.83%
|
335/30-18
d=25.91
w=3.96
-17.64%
|
335/35-18
d=27.23
w=4.62
-13.45%
|
335/40-18
d=28.55
w=5.28
-9.26%
|
335/45-18
d=29.87
w=5.94
-5.07%
|
335/50-18
d=31.19
w=6.59
-0.88%
|
335/55-18
d=32.51
w=7.25
+3.32%
|
335/60-18
d=33.83
w=7.91
+7.51%
|
335/65-18
d=35.15
w=8.57
+11.70%
|
335/70-18
d=36.46
w=9.23
+15.89%
|
335/75-18
d=37.78
w=9.89
+20.08%
|
335/80-18
d=39.10
w=10.55
+24.27%
|
335/85-18
d=40.42
w=11.21
+28.47%
|
|
Wheel Size 19
|
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|
Wheel Size 20
|
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|
Wheel Size 21
|
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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!