| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 225/60-18 | 0.00 % | 50.00 | 1,000.00 | 28.63 | 5.31 | 135.00 |
| 245/55-18 | -0.07 % | 49.97 | 1,000.69 | 28.61 | 5.31 | 134.75 |
| 335/40-18 | -0.28 % | 49.86 | 1,002.75 | 28.55 | 5.28 | 134.00 |
| 195/70-18 | +0.41 % | 50.21 | 995.87 | 28.75 | 5.37 | 136.50 |
| 205/65-18 | -0.48 % | 49.76 | 1,004.81 | 28.49 | 5.25 | 133.25 |
| 295/45-18 | -0.62 % | 49.69 | 1,006.19 | 28.45 | 5.23 | 132.75 |
| 305/45-18 | +0.62 % | 50.31 | 993.81 | 28.81 | 5.40 | 137.25 |
| 265/50-18 | -0.69 % | 49.66 | 1,006.88 | 28.43 | 5.22 | 132.50 |
| 275/50-18 | +0.69 % | 50.34 | 993.12 | 28.83 | 5.41 | 137.50 |
| 165/80-18 | -0.83 % | 49.59 | 1,008.25 | 28.39 | 5.20 | 132.00 |
| 155/85-18 | -0.89 % | 49.55 | 1,008.94 | 28.37 | 5.19 | 131.75 |
| 175/75-18 | -1.03 % | 49.48 | 1,010.31 | 28.33 | 5.17 | 131.25 |
| 185/75-18 | +1.03 % | 50.52 | 989.69 | 28.93 | 5.46 | 138.75 |
| 215/65-18 | +1.31 % | 50.65 | 986.94 | 29.00 | 5.50 | 139.75 |
| 325/40-18 | -1.38 % | 49.31 | 1,013.75 | 28.24 | 5.12 | 130.00 |
| 175/80-18 | +1.38 % | 50.69 | 986.25 | 29.02 | 5.51 | 140.00 |
| 255/55-18 | +1.44 % | 50.72 | 985.56 | 29.04 | 5.52 | 140.25 |
| 165/85-18 | +1.44 % | 50.72 | 985.56 | 29.04 | 5.52 | 140.25 |
| 185/70-18 | -1.51 % | 49.24 | 1,015.13 | 28.20 | 5.10 | 129.50 |
| 235/55-18 | -1.58 % | 49.21 | 1,015.81 | 28.18 | 5.09 | 129.25 |
| 235/60-18 | +1.65 % | 50.83 | 983.50 | 29.10 | 5.55 | 141.00 |
| 215/60-18 | -1.65 % | 49.17 | 1,016.50 | 28.16 | 5.08 | 129.00 |
| 315/45-18 | +1.86 % | 50.93 | 981.44 | 29.16 | 5.58 | 141.75 |
| 285/45-18 | -1.86 % | 49.07 | 1,018.56 | 28.10 | 5.05 | 128.25 |
| 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
-27.16%
|
145/30-18
d=21.43
w=1.71
-25.17%
|
145/35-18
d=22.00
w=2.00
-23.17%
|
145/40-18
d=22.57
w=2.28
-21.18%
|
145/45-18
d=23.14
w=2.57
-19.18%
|
145/50-18
d=23.71
w=2.85
-17.19%
|
145/55-18
d=24.28
w=3.14
-15.20%
|
145/60-18
d=24.85
w=3.43
-13.20%
|
145/65-18
d=25.42
w=3.71
-11.21%
|
145/70-18
d=25.99
w=4.00
-9.21%
|
145/75-18
d=26.56
w=4.28
-7.22%
|
145/80-18
d=27.13
w=4.57
-5.23%
|
145/85-18
d=27.70
w=4.85
-3.23%
|
| 155 |
155/25-18
d=21.05
w=1.53
-26.47%
|
155/30-18
d=21.66
w=1.83
-24.34%
|
155/35-18
d=22.27
w=2.14
-22.21%
|
155/40-18
d=22.88
w=2.44
-20.08%
|
155/45-18
d=23.49
w=2.75
-17.95%
|
155/50-18
d=24.10
w=3.05
-15.81%
|
155/55-18
d=24.71
w=3.36
-13.68%
|
155/60-18
d=25.32
w=3.66
-11.55%
|
155/65-18
d=25.93
w=3.97
-9.42%
|
155/70-18
d=26.54
w=4.27
-7.29%
|
155/75-18
d=27.15
w=4.58
-5.16%
|
155/80-18
d=27.76
w=4.88
-3.03%
|
155/85-18
d=28.37
w=5.19
-0.89%
|
| 165 |
165/25-18
d=21.25
w=1.62
-25.78%
|
165/30-18
d=21.90
w=1.95
-23.51%
|
165/35-18
d=22.55
w=2.27
-21.25%
|
165/40-18
d=23.20
w=2.60
-18.98%
|
165/45-18
d=23.85
w=2.92
-16.71%
|
165/50-18
d=24.50
w=3.25
-14.44%
|
165/55-18
d=25.15
w=3.57
-12.17%
|
165/60-18
d=25.80
w=3.90
-9.90%
|
165/65-18
d=26.44
w=4.22
-7.63%
|
165/70-18
d=27.09
w=4.55
-5.36%
|
165/75-18
d=27.74
w=4.87
-3.09%
|
165/80-18
d=28.39
w=5.20
-0.83%
|
165/85-18
d=29.04
w=5.52
+1.44%
|
| 175 |
175/25-18
d=21.44
w=1.72
-25.10%
|
175/30-18
d=22.13
w=2.07
-22.69%
|
175/35-18
d=22.82
w=2.41
-20.28%
|
175/40-18
d=23.51
w=2.76
-17.88%
|
175/45-18
d=24.20
w=3.10
-15.47%
|
175/50-18
d=24.89
w=3.44
-13.06%
|
175/55-18
d=25.58
w=3.79
-10.66%
|
175/60-18
d=26.27
w=4.13
-8.25%
|
175/65-18
d=26.96
w=4.48
-5.84%
|
175/70-18
d=27.65
w=4.82
-3.44%
|
175/75-18
d=28.33
w=5.17
-1.03%
|
175/80-18
d=29.02
w=5.51
+1.38%
|
175/85-18
d=29.71
w=5.86
+3.78%
|
| 185 |
185/25-18
d=21.64
w=1.82
-24.41%
|
185/30-18
d=22.37
w=2.19
-21.86%
|
185/35-18
d=23.10
w=2.55
-19.32%
|
185/40-18
d=23.83
w=2.91
-16.78%
|
185/45-18
d=24.56
w=3.28
-14.23%
|
185/50-18
d=25.28
w=3.64
-11.69%
|
185/55-18
d=26.01
w=4.01
-9.14%
|
185/60-18
d=26.74
w=4.37
-6.60%
|
185/65-18
d=27.47
w=4.73
-4.06%
|
185/70-18
d=28.20
w=5.10
-1.51%
|
185/75-18
d=28.93
w=5.46
+1.03%
|
185/80-18
d=29.65
w=5.83
+3.58%
|
185/85-18
d=30.38
w=6.19
+6.12%
|
| 195 |
195/25-18
d=21.84
w=1.92
-23.72%
|
195/30-18
d=22.61
w=2.30
-21.04%
|
195/35-18
d=23.37
w=2.69
-18.36%
|
195/40-18
d=24.14
w=3.07
-15.68%
|
195/45-18
d=24.91
w=3.45
-13.00%
|
195/50-18
d=25.68
w=3.84
-10.31%
|
195/55-18
d=26.44
w=4.22
-7.63%
|
195/60-18
d=27.21
w=4.61
-4.95%
|
195/65-18
d=27.98
w=4.99
-2.27%
|
195/70-18
d=28.75
w=5.37
+0.41%
|
195/75-18
d=29.52
w=5.76
+3.09%
|
195/80-18
d=30.28
w=6.14
+5.78%
|
195/85-18
d=31.05
w=6.53
+8.46%
|
| 205 |
205/25-18
d=22.04
w=2.02
-23.03%
|
205/30-18
d=22.84
w=2.42
-20.21%
|
205/35-18
d=23.65
w=2.82
-17.40%
|
205/40-18
d=24.46
w=3.23
-14.58%
|
205/45-18
d=25.26
w=3.63
-11.76%
|
205/50-18
d=26.07
w=4.04
-8.94%
|
205/55-18
d=26.88
w=4.44
-6.12%
|
205/60-18
d=27.69
w=4.84
-3.30%
|
205/65-18
d=28.49
w=5.25
-0.48%
|
205/70-18
d=29.30
w=5.65
+2.34%
|
205/75-18
d=30.11
w=6.05
+5.16%
|
205/80-18
d=30.91
w=6.46
+7.98%
|
205/85-18
d=31.72
w=6.86
+10.79%
|
| 215 |
215/25-18
d=22.23
w=2.12
-22.35%
|
215/30-18
d=23.08
w=2.54
-19.39%
|
215/35-18
d=23.93
w=2.96
-16.43%
|
215/40-18
d=24.77
w=3.39
-13.48%
|
215/45-18
d=25.62
w=3.81
-10.52%
|
215/50-18
d=26.46
w=4.23
-7.56%
|
215/55-18
d=27.31
w=4.66
-4.61%
|
215/60-18
d=28.16
w=5.08
-1.65%
|
215/65-18
d=29.00
w=5.50
+1.31%
|
215/70-18
d=29.85
w=5.93
+4.26%
|
215/75-18
d=30.70
w=6.35
+7.22%
|
215/80-18
d=31.54
w=6.77
+10.18%
|
215/85-18
d=32.39
w=7.19
+13.13%
|
| 225 |
225/25-18
d=22.43
w=2.21
-21.66%
|
225/30-18
d=23.31
w=2.66
-18.56%
|
225/35-18
d=24.20
w=3.10
-15.47%
|
225/40-18
d=25.09
w=3.54
-12.38%
|
225/45-18
d=25.97
w=3.99
-9.28%
|
225/50-18
d=26.86
w=4.43
-6.19%
|
225/55-18
d=27.74
w=4.87
-3.09%
|
225/60-18
d=28.63
w=5.31
0.00%
|
225/65-18
d=29.52
w=5.76
+3.09%
|
225/70-18
d=30.40
w=6.20
+6.19%
|
225/75-18
d=31.29
w=6.64
+9.28%
|
225/80-18
d=32.17
w=7.09
+12.38%
|
225/85-18
d=33.06
w=7.53
+15.47%
|
| 235 |
235/25-18
d=22.63
w=2.31
-20.97%
|
235/30-18
d=23.55
w=2.78
-17.74%
|
235/35-18
d=24.48
w=3.24
-14.51%
|
235/40-18
d=25.40
w=3.70
-11.28%
|
235/45-18
d=26.33
w=4.16
-8.04%
|
235/50-18
d=27.25
w=4.63
-4.81%
|
235/55-18
d=28.18
w=5.09
-1.58%
|
235/60-18
d=29.10
w=5.55
+1.65%
|
235/65-18
d=30.03
w=6.01
+4.88%
|
235/70-18
d=30.95
w=6.48
+8.11%
|
235/75-18
d=31.88
w=6.94
+11.34%
|
235/80-18
d=32.80
w=7.40
+14.58%
|
235/85-18
d=33.73
w=7.86
+17.81%
|
| 245 |
245/25-18
d=22.82
w=2.41
-20.28%
|
245/30-18
d=23.79
w=2.89
-16.91%
|
245/35-18
d=24.75
w=3.38
-13.55%
|
245/40-18
d=25.72
w=3.86
-10.18%
|
245/45-18
d=26.68
w=4.34
-6.81%
|
245/50-18
d=27.65
w=4.82
-3.44%
|
245/55-18
d=28.61
w=5.31
-0.07%
|
245/60-18
d=29.57
w=5.79
+3.30%
|
245/65-18
d=30.54
w=6.27
+6.67%
|
245/70-18
d=31.50
w=6.75
+10.04%
|
245/75-18
d=32.47
w=7.23
+13.41%
|
245/80-18
d=33.43
w=7.72
+16.78%
|
245/85-18
d=34.40
w=8.20
+20.15%
|
| 255 |
255/25-18
d=23.02
w=2.51
-19.60%
|
255/30-18
d=24.02
w=3.01
-16.09%
|
255/35-18
d=25.03
w=3.51
-12.58%
|
255/40-18
d=26.03
w=4.02
-9.08%
|
255/45-18
d=27.04
w=4.52
-5.57%
|
255/50-18
d=28.04
w=5.02
-2.06%
|
255/55-18
d=29.04
w=5.52
+1.44%
|
255/60-18
d=30.05
w=6.02
+4.95%
|
255/65-18
d=31.05
w=6.53
+8.46%
|
255/70-18
d=32.06
w=7.03
+11.96%
|
255/75-18
d=33.06
w=7.53
+15.47%
|
255/80-18
d=34.06
w=8.03
+18.98%
|
255/85-18
d=35.07
w=8.53
+22.48%
|
| 265 |
265/25-18
d=23.22
w=2.61
-18.91%
|
265/30-18
d=24.26
w=3.13
-15.26%
|
265/35-18
d=25.30
w=3.65
-11.62%
|
265/40-18
d=26.35
w=4.17
-7.98%
|
265/45-18
d=27.39
w=4.69
-4.33%
|
265/50-18
d=28.43
w=5.22
-0.69%
|
265/55-18
d=29.48
w=5.74
+2.96%
|
265/60-18
d=30.52
w=6.26
+6.60%
|
265/65-18
d=31.56
w=6.78
+10.24%
|
265/70-18
d=32.61
w=7.30
+13.89%
|
265/75-18
d=33.65
w=7.82
+17.53%
|
265/80-18
d=34.69
w=8.35
+21.18%
|
265/85-18
d=35.74
w=8.87
+24.82%
|
| 275 |
275/25-18
d=23.41
w=2.71
-18.22%
|
275/30-18
d=24.50
w=3.25
-14.44%
|
275/35-18
d=25.58
w=3.79
-10.66%
|
275/40-18
d=26.66
w=4.33
-6.88%
|
275/45-18
d=27.74
w=4.87
-3.09%
|
275/50-18
d=28.83
w=5.41
+0.69%
|
275/55-18
d=29.91
w=5.95
+4.47%
|
275/60-18
d=30.99
w=6.50
+8.25%
|
275/65-18
d=32.07
w=7.04
+12.03%
|
275/70-18
d=33.16
w=7.58
+15.81%
|
275/75-18
d=34.24
w=8.12
+19.60%
|
275/80-18
d=35.32
w=8.66
+23.38%
|
275/85-18
d=36.41
w=9.20
+27.16%
|
| 285 |
285/25-18
d=23.61
w=2.81
-17.53%
|
285/30-18
d=24.73
w=3.37
-13.61%
|
285/35-18
d=25.85
w=3.93
-9.69%
|
285/40-18
d=26.98
w=4.49
-5.78%
|
285/45-18
d=28.10
w=5.05
-1.86%
|
285/50-18
d=29.22
w=5.61
+2.06%
|
285/55-18
d=30.34
w=6.17
+5.98%
|
285/60-18
d=31.46
w=6.73
+9.90%
|
285/65-18
d=32.59
w=7.29
+13.82%
|
285/70-18
d=33.71
w=7.85
+17.74%
|
285/75-18
d=34.83
w=8.42
+21.66%
|
285/80-18
d=35.95
w=8.98
+25.58%
|
285/85-18
d=37.07
w=9.54
+29.50%
|
| 295 |
295/25-18
d=23.81
w=2.90
-16.85%
|
295/30-18
d=24.97
w=3.48
-12.79%
|
295/35-18
d=26.13
w=4.06
-8.73%
|
295/40-18
d=27.29
w=4.65
-4.68%
|
295/45-18
d=28.45
w=5.23
-0.62%
|
295/50-18
d=29.61
w=5.81
+3.44%
|
295/55-18
d=30.78
w=6.39
+7.49%
|
295/60-18
d=31.94
w=6.97
+11.55%
|
295/65-18
d=33.10
w=7.55
+15.61%
|
295/70-18
d=34.26
w=8.13
+19.66%
|
295/75-18
d=35.42
w=8.71
+23.72%
|
295/80-18
d=36.58
w=9.29
+27.78%
|
295/85-18
d=37.74
w=9.87
+31.83%
|
| 305 |
305/25-18
d=24.00
w=3.00
-16.16%
|
305/30-18
d=25.20
w=3.60
-11.96%
|
305/35-18
d=26.41
w=4.20
-7.77%
|
305/40-18
d=27.61
w=4.80
-3.58%
|
305/45-18
d=28.81
w=5.40
+0.62%
|
305/50-18
d=30.01
w=6.00
+4.81%
|
305/55-18
d=31.21
w=6.60
+9.01%
|
305/60-18
d=32.41
w=7.20
+13.20%
|
305/65-18
d=33.61
w=7.81
+17.40%
|
305/70-18
d=34.81
w=8.41
+21.59%
|
305/75-18
d=36.01
w=9.01
+25.78%
|
305/80-18
d=37.21
w=9.61
+29.98%
|
305/85-18
d=38.41
w=10.21
+34.17%
|
| 315 |
315/25-18
d=24.20
w=3.10
-15.47%
|
315/30-18
d=25.44
w=3.72
-11.14%
|
315/35-18
d=26.68
w=4.34
-6.81%
|
315/40-18
d=27.92
w=4.96
-2.48%
|
315/45-18
d=29.16
w=5.58
+1.86%
|
315/50-18
d=30.40
w=6.20
+6.19%
|
315/55-18
d=31.64
w=6.82
+10.52%
|
315/60-18
d=32.88
w=7.44
+14.85%
|
315/65-18
d=34.12
w=8.06
+19.18%
|
315/70-18
d=35.36
w=8.68
+23.51%
|
315/75-18
d=36.60
w=9.30
+27.85%
|
315/80-18
d=37.84
w=9.92
+32.18%
|
315/85-18
d=39.08
w=10.54
+36.51%
|
| 325 |
325/25-18
d=24.40
w=3.20
-14.78%
|
325/30-18
d=25.68
w=3.84
-10.31%
|
325/35-18
d=26.96
w=4.48
-5.84%
|
325/40-18
d=28.24
w=5.12
-1.38%
|
325/45-18
d=29.52
w=5.76
+3.09%
|
325/50-18
d=30.80
w=6.40
+7.56%
|
325/55-18
d=32.07
w=7.04
+12.03%
|
325/60-18
d=33.35
w=7.68
+16.50%
|
325/65-18
d=34.63
w=8.32
+20.97%
|
325/70-18
d=35.91
w=8.96
+25.44%
|
325/75-18
d=37.19
w=9.60
+29.91%
|
325/80-18
d=38.47
w=10.24
+34.38%
|
325/85-18
d=39.75
w=10.88
+38.85%
|
| 335 |
335/25-18
d=24.59
w=3.30
-14.10%
|
335/30-18
d=25.91
w=3.96
-9.49%
|
335/35-18
d=27.23
w=4.62
-4.88%
|
335/40-18
d=28.55
w=5.28
-0.28%
|
335/45-18
d=29.87
w=5.94
+4.33%
|
335/50-18
d=31.19
w=6.59
+8.94%
|
335/55-18
d=32.51
w=7.25
+13.55%
|
335/60-18
d=33.83
w=7.91
+18.15%
|
335/65-18
d=35.15
w=8.57
+22.76%
|
335/70-18
d=36.46
w=9.23
+27.37%
|
335/75-18
d=37.78
w=9.89
+31.97%
|
335/80-18
d=39.10
w=10.55
+36.58%
|
335/85-18
d=40.42
w=11.21
+41.19%
|
|
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!