| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 235/55-20 | 0.00 % | 50.00 | 1,000.00 | 30.18 | 5.09 | 129.25 |
| 215/60-20 | -0.07 % | 49.97 | 1,000.65 | 30.16 | 5.08 | 129.00 |
| 185/70-20 | +0.07 % | 50.03 | 999.35 | 30.20 | 5.10 | 129.50 |
| 325/40-20 | +0.20 % | 50.10 | 998.04 | 30.24 | 5.12 | 130.00 |
| 285/45-20 | -0.26 % | 49.87 | 1,002.61 | 30.10 | 5.05 | 128.25 |
| 255/50-20 | -0.46 % | 49.77 | 1,004.57 | 30.04 | 5.02 | 127.50 |
| 175/75-20 | +0.52 % | 50.26 | 994.78 | 30.33 | 5.17 | 131.25 |
| 155/85-20 | +0.65 % | 50.33 | 993.48 | 30.37 | 5.19 | 131.75 |
| 195/65-20 | -0.65 % | 49.67 | 1,006.52 | 29.98 | 4.99 | 126.75 |
| 165/80-20 | +0.72 % | 50.36 | 992.82 | 30.39 | 5.20 | 132.00 |
| 315/40-20 | -0.85 % | 49.58 | 1,008.48 | 29.92 | 4.96 | 126.00 |
| 265/50-20 | +0.85 % | 50.42 | 991.52 | 30.43 | 5.22 | 132.50 |
| 295/45-20 | +0.91 % | 50.46 | 990.87 | 30.45 | 5.23 | 132.75 |
| 205/65-20 | +1.04 % | 50.52 | 989.56 | 30.49 | 5.25 | 133.25 |
| 335/40-20 | +1.24 % | 50.62 | 987.61 | 30.55 | 5.28 | 134.00 |
| 155/80-20 | -1.37 % | 49.32 | 1,013.70 | 29.76 | 4.88 | 124.00 |
| 245/55-20 | +1.44 % | 50.72 | 985.65 | 30.61 | 5.31 | 134.75 |
| 275/45-20 | -1.44 % | 49.28 | 1,014.35 | 29.74 | 4.87 | 123.75 |
| 225/55-20 | -1.44 % | 49.28 | 1,014.35 | 29.74 | 4.87 | 123.75 |
| 165/75-20 | -1.44 % | 49.28 | 1,014.35 | 29.74 | 4.87 | 123.75 |
| 225/60-20 | +1.50 % | 50.75 | 985.00 | 30.63 | 5.31 | 135.00 |
| 145/85-20 | -1.57 % | 49.22 | 1,015.66 | 29.70 | 4.85 | 123.25 |
| 205/60-20 | -1.63 % | 49.18 | 1,016.31 | 29.69 | 4.84 | 123.00 |
| 245/50-20 | -1.76 % | 49.12 | 1,017.61 | 29.65 | 4.82 | 122.50 |
| 175/70-20 | -1.76 % | 49.12 | 1,017.61 | 29.65 | 4.82 | 122.50 |
| 195/70-20 | +1.89 % | 50.95 | 981.08 | 30.75 | 5.37 | 136.50 |
| 305/40-20 | -1.89 % | 49.05 | 1,018.92 | 29.61 | 4.80 | 122.00 |
| Ratio: | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Wheel Size 12
|
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|
Wheel Size 13
|
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|
Wheel Size 14
|
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|
Wheel Size 15
|
|||||||||||||
|
Wheel Size 16
|
|||||||||||||
|
Wheel Size 16.5
|
|||||||||||||
|
Wheel Size 17
|
|||||||||||||
|
Wheel Size 18
|
|||||||||||||
|
Wheel Size 19
|
|||||||||||||
|
Wheel Size 20
|
|||||||||||||
| 145 |
145/25-20
d=22.85
w=1.43
-24.27%
|
145/30-20
d=23.43
w=1.71
-22.37%
|
145/35-20
d=24.00
w=2.00
-20.48%
|
145/40-20
d=24.57
w=2.28
-18.59%
|
145/45-20
d=25.14
w=2.57
-16.70%
|
145/50-20
d=25.71
w=2.85
-14.81%
|
145/55-20
d=26.28
w=3.14
-12.92%
|
145/60-20
d=26.85
w=3.43
-11.02%
|
145/65-20
d=27.42
w=3.71
-9.13%
|
145/70-20
d=27.99
w=4.00
-7.24%
|
145/75-20
d=28.56
w=4.28
-5.35%
|
145/80-20
d=29.13
w=4.57
-3.46%
|
145/85-20
d=29.70
w=4.85
-1.57%
|
| 155 |
155/25-20
d=23.05
w=1.53
-23.61%
|
155/30-20
d=23.66
w=1.83
-21.59%
|
155/35-20
d=24.27
w=2.14
-19.57%
|
155/40-20
d=24.88
w=2.44
-17.55%
|
155/45-20
d=25.49
w=2.75
-15.53%
|
155/50-20
d=26.10
w=3.05
-13.50%
|
155/55-20
d=26.71
w=3.36
-11.48%
|
155/60-20
d=27.32
w=3.66
-9.46%
|
155/65-20
d=27.93
w=3.97
-7.44%
|
155/70-20
d=28.54
w=4.27
-5.41%
|
155/75-20
d=29.15
w=4.58
-3.39%
|
155/80-20
d=29.76
w=4.88
-1.37%
|
155/85-20
d=30.37
w=5.19
+0.65%
|
| 165 |
165/25-20
d=23.25
w=1.62
-22.96%
|
165/30-20
d=23.90
w=1.95
-20.81%
|
165/35-20
d=24.55
w=2.27
-18.66%
|
165/40-20
d=25.20
w=2.60
-16.50%
|
165/45-20
d=25.85
w=2.92
-14.35%
|
165/50-20
d=26.50
w=3.25
-12.20%
|
165/55-20
d=27.15
w=3.57
-10.05%
|
165/60-20
d=27.80
w=3.90
-7.89%
|
165/65-20
d=28.44
w=4.22
-5.74%
|
165/70-20
d=29.09
w=4.55
-3.59%
|
165/75-20
d=29.74
w=4.87
-1.44%
|
165/80-20
d=30.39
w=5.20
+0.72%
|
165/85-20
d=31.04
w=5.52
+2.87%
|
| 175 |
175/25-20
d=23.44
w=1.72
-22.31%
|
175/30-20
d=24.13
w=2.07
-20.03%
|
175/35-20
d=24.82
w=2.41
-17.74%
|
175/40-20
d=25.51
w=2.76
-15.46%
|
175/45-20
d=26.20
w=3.10
-13.18%
|
175/50-20
d=26.89
w=3.44
-10.89%
|
175/55-20
d=27.58
w=3.79
-8.61%
|
175/60-20
d=28.27
w=4.13
-6.33%
|
175/65-20
d=28.96
w=4.48
-4.04%
|
175/70-20
d=29.65
w=4.82
-1.76%
|
175/75-20
d=30.33
w=5.17
+0.52%
|
175/80-20
d=31.02
w=5.51
+2.80%
|
175/85-20
d=31.71
w=5.86
+5.09%
|
| 185 |
185/25-20
d=23.64
w=1.82
-21.66%
|
185/30-20
d=24.37
w=2.19
-19.24%
|
185/35-20
d=25.10
w=2.55
-16.83%
|
185/40-20
d=25.83
w=2.91
-14.42%
|
185/45-20
d=26.56
w=3.28
-12.00%
|
185/50-20
d=27.28
w=3.64
-9.59%
|
185/55-20
d=28.01
w=4.01
-7.18%
|
185/60-20
d=28.74
w=4.37
-4.76%
|
185/65-20
d=29.47
w=4.73
-2.35%
|
185/70-20
d=30.20
w=5.10
+0.07%
|
185/75-20
d=30.93
w=5.46
+2.48%
|
185/80-20
d=31.65
w=5.83
+4.89%
|
185/85-20
d=32.38
w=6.19
+7.31%
|
| 195 |
195/25-20
d=23.84
w=1.92
-21.00%
|
195/30-20
d=24.61
w=2.30
-18.46%
|
195/35-20
d=25.37
w=2.69
-15.92%
|
195/40-20
d=26.14
w=3.07
-13.37%
|
195/45-20
d=26.91
w=3.45
-10.83%
|
195/50-20
d=27.68
w=3.84
-8.28%
|
195/55-20
d=28.44
w=4.22
-5.74%
|
195/60-20
d=29.21
w=4.61
-3.20%
|
195/65-20
d=29.98
w=4.99
-0.65%
|
195/70-20
d=30.75
w=5.37
+1.89%
|
195/75-20
d=31.52
w=5.76
+4.44%
|
195/80-20
d=32.28
w=6.14
+6.98%
|
195/85-20
d=33.05
w=6.53
+9.52%
|
| 205 |
205/25-20
d=24.04
w=2.02
-20.35%
|
205/30-20
d=24.84
w=2.42
-17.68%
|
205/35-20
d=25.65
w=2.82
-15.00%
|
205/40-20
d=26.46
w=3.23
-12.33%
|
205/45-20
d=27.26
w=3.63
-9.65%
|
205/50-20
d=28.07
w=4.04
-6.98%
|
205/55-20
d=28.88
w=4.44
-4.31%
|
205/60-20
d=29.69
w=4.84
-1.63%
|
205/65-20
d=30.49
w=5.25
+1.04%
|
205/70-20
d=31.30
w=5.65
+3.72%
|
205/75-20
d=32.11
w=6.05
+6.39%
|
205/80-20
d=32.91
w=6.46
+9.07%
|
205/85-20
d=33.72
w=6.86
+11.74%
|
| 215 |
215/25-20
d=24.23
w=2.12
-19.70%
|
215/30-20
d=25.08
w=2.54
-16.89%
|
215/35-20
d=25.93
w=2.96
-14.09%
|
215/40-20
d=26.77
w=3.39
-11.29%
|
215/45-20
d=27.62
w=3.81
-8.48%
|
215/50-20
d=28.46
w=4.23
-5.68%
|
215/55-20
d=29.31
w=4.66
-2.87%
|
215/60-20
d=30.16
w=5.08
-0.07%
|
215/65-20
d=31.00
w=5.50
+2.74%
|
215/70-20
d=31.85
w=5.93
+5.54%
|
215/75-20
d=32.70
w=6.35
+8.35%
|
215/80-20
d=33.54
w=6.77
+11.15%
|
215/85-20
d=34.39
w=7.19
+13.96%
|
| 225 |
225/25-20
d=24.43
w=2.21
-19.05%
|
225/30-20
d=25.31
w=2.66
-16.11%
|
225/35-20
d=26.20
w=3.10
-13.18%
|
225/40-20
d=27.09
w=3.54
-10.24%
|
225/45-20
d=27.97
w=3.99
-7.31%
|
225/50-20
d=28.86
w=4.43
-4.37%
|
225/55-20
d=29.74
w=4.87
-1.44%
|
225/60-20
d=30.63
w=5.31
+1.50%
|
225/65-20
d=31.52
w=5.76
+4.44%
|
225/70-20
d=32.40
w=6.20
+7.37%
|
225/75-20
d=33.29
w=6.64
+10.31%
|
225/80-20
d=34.17
w=7.09
+13.24%
|
225/85-20
d=35.06
w=7.53
+16.18%
|
| 235 |
235/25-20
d=24.63
w=2.31
-18.40%
|
235/30-20
d=25.55
w=2.78
-15.33%
|
235/35-20
d=26.48
w=3.24
-12.26%
|
235/40-20
d=27.40
w=3.70
-9.20%
|
235/45-20
d=28.33
w=4.16
-6.13%
|
235/50-20
d=29.25
w=4.63
-3.07%
|
235/55-20
d=30.18
w=5.09
0.00%
|
235/60-20
d=31.10
w=5.55
+3.07%
|
235/65-20
d=32.03
w=6.01
+6.13%
|
235/70-20
d=32.95
w=6.48
+9.20%
|
235/75-20
d=33.88
w=6.94
+12.26%
|
235/80-20
d=34.80
w=7.40
+15.33%
|
235/85-20
d=35.73
w=7.86
+18.40%
|
| 245 |
245/25-20
d=24.82
w=2.41
-17.74%
|
245/30-20
d=25.79
w=2.89
-14.55%
|
245/35-20
d=26.75
w=3.38
-11.35%
|
245/40-20
d=27.72
w=3.86
-8.15%
|
245/45-20
d=28.68
w=4.34
-4.96%
|
245/50-20
d=29.65
w=4.82
-1.76%
|
245/55-20
d=30.61
w=5.31
+1.44%
|
245/60-20
d=31.57
w=5.79
+4.63%
|
245/65-20
d=32.54
w=6.27
+7.83%
|
245/70-20
d=33.50
w=6.75
+11.02%
|
245/75-20
d=34.47
w=7.23
+14.22%
|
245/80-20
d=35.43
w=7.72
+17.42%
|
245/85-20
d=36.40
w=8.20
+20.61%
|
| 255 |
255/25-20
d=25.02
w=2.51
-17.09%
|
255/30-20
d=26.02
w=3.01
-13.76%
|
255/35-20
d=27.03
w=3.51
-10.44%
|
255/40-20
d=28.03
w=4.02
-7.11%
|
255/45-20
d=29.04
w=4.52
-3.78%
|
255/50-20
d=30.04
w=5.02
-0.46%
|
255/55-20
d=31.04
w=5.52
+2.87%
|
255/60-20
d=32.05
w=6.02
+6.20%
|
255/65-20
d=33.05
w=6.53
+9.52%
|
255/70-20
d=34.06
w=7.03
+12.85%
|
255/75-20
d=35.06
w=7.53
+16.18%
|
255/80-20
d=36.06
w=8.03
+19.50%
|
255/85-20
d=37.07
w=8.53
+22.83%
|
| 265 |
265/25-20
d=25.22
w=2.61
-16.44%
|
265/30-20
d=26.26
w=3.13
-12.98%
|
265/35-20
d=27.30
w=3.65
-9.52%
|
265/40-20
d=28.35
w=4.17
-6.07%
|
265/45-20
d=29.39
w=4.69
-2.61%
|
265/50-20
d=30.43
w=5.22
+0.85%
|
265/55-20
d=31.48
w=5.74
+4.31%
|
265/60-20
d=32.52
w=6.26
+7.76%
|
265/65-20
d=33.56
w=6.78
+11.22%
|
265/70-20
d=34.61
w=7.30
+14.68%
|
265/75-20
d=35.65
w=7.82
+18.13%
|
265/80-20
d=36.69
w=8.35
+21.59%
|
265/85-20
d=37.74
w=8.87
+25.05%
|
| 275 |
275/25-20
d=25.41
w=2.71
-15.79%
|
275/30-20
d=26.50
w=3.25
-12.20%
|
275/35-20
d=27.58
w=3.79
-8.61%
|
275/40-20
d=28.66
w=4.33
-5.02%
|
275/45-20
d=29.74
w=4.87
-1.44%
|
275/50-20
d=30.83
w=5.41
+2.15%
|
275/55-20
d=31.91
w=5.95
+5.74%
|
275/60-20
d=32.99
w=6.50
+9.33%
|
275/65-20
d=34.07
w=7.04
+12.92%
|
275/70-20
d=35.16
w=7.58
+16.50%
|
275/75-20
d=36.24
w=8.12
+20.09%
|
275/80-20
d=37.32
w=8.66
+23.68%
|
275/85-20
d=38.41
w=9.20
+27.27%
|
| 285 |
285/25-20
d=25.61
w=2.81
-15.13%
|
285/30-20
d=26.73
w=3.37
-11.42%
|
285/35-20
d=27.85
w=3.93
-7.70%
|
285/40-20
d=28.98
w=4.49
-3.98%
|
285/45-20
d=30.10
w=5.05
-0.26%
|
285/50-20
d=31.22
w=5.61
+3.46%
|
285/55-20
d=32.34
w=6.17
+7.18%
|
285/60-20
d=33.46
w=6.73
+10.89%
|
285/65-20
d=34.59
w=7.29
+14.61%
|
285/70-20
d=35.71
w=7.85
+18.33%
|
285/75-20
d=36.83
w=8.42
+22.05%
|
285/80-20
d=37.95
w=8.98
+25.77%
|
285/85-20
d=39.07
w=9.54
+29.48%
|
| 295 |
295/25-20
d=25.81
w=2.90
-14.48%
|
295/30-20
d=26.97
w=3.48
-10.63%
|
295/35-20
d=28.13
w=4.06
-6.78%
|
295/40-20
d=29.29
w=4.65
-2.94%
|
295/45-20
d=30.45
w=5.23
+0.91%
|
295/50-20
d=31.61
w=5.81
+4.76%
|
295/55-20
d=32.78
w=6.39
+8.61%
|
295/60-20
d=33.94
w=6.97
+12.46%
|
295/65-20
d=35.10
w=7.55
+16.31%
|
295/70-20
d=36.26
w=8.13
+20.16%
|
295/75-20
d=37.42
w=8.71
+24.01%
|
295/80-20
d=38.58
w=9.29
+27.85%
|
295/85-20
d=39.74
w=9.87
+31.70%
|
| 305 |
305/25-20
d=26.00
w=3.00
-13.83%
|
305/30-20
d=27.20
w=3.60
-9.85%
|
305/35-20
d=28.41
w=4.20
-5.87%
|
305/40-20
d=29.61
w=4.80
-1.89%
|
305/45-20
d=30.81
w=5.40
+2.09%
|
305/50-20
d=32.01
w=6.00
+6.07%
|
305/55-20
d=33.21
w=6.60
+10.05%
|
305/60-20
d=34.41
w=7.20
+14.02%
|
305/65-20
d=35.61
w=7.81
+18.00%
|
305/70-20
d=36.81
w=8.41
+21.98%
|
305/75-20
d=38.01
w=9.01
+25.96%
|
305/80-20
d=39.21
w=9.61
+29.94%
|
305/85-20
d=40.41
w=10.21
+33.92%
|
| 315 |
315/25-20
d=26.20
w=3.10
-13.18%
|
315/30-20
d=27.44
w=3.72
-9.07%
|
315/35-20
d=28.68
w=4.34
-4.96%
|
315/40-20
d=29.92
w=4.96
-0.85%
|
315/45-20
d=31.16
w=5.58
+3.26%
|
315/50-20
d=32.40
w=6.20
+7.37%
|
315/55-20
d=33.64
w=6.82
+11.48%
|
315/60-20
d=34.88
w=7.44
+15.59%
|
315/65-20
d=36.12
w=8.06
+19.70%
|
315/70-20
d=37.36
w=8.68
+23.81%
|
315/75-20
d=38.60
w=9.30
+27.92%
|
315/80-20
d=39.84
w=9.92
+32.03%
|
315/85-20
d=41.08
w=10.54
+36.14%
|
| 325 |
325/25-20
d=26.40
w=3.20
-12.52%
|
325/30-20
d=27.68
w=3.84
-8.28%
|
325/35-20
d=28.96
w=4.48
-4.04%
|
325/40-20
d=30.24
w=5.12
+0.20%
|
325/45-20
d=31.52
w=5.76
+4.44%
|
325/50-20
d=32.80
w=6.40
+8.68%
|
325/55-20
d=34.07
w=7.04
+12.92%
|
325/60-20
d=35.35
w=7.68
+17.16%
|
325/65-20
d=36.63
w=8.32
+21.40%
|
325/70-20
d=37.91
w=8.96
+25.64%
|
325/75-20
d=39.19
w=9.60
+29.88%
|
325/80-20
d=40.47
w=10.24
+34.12%
|
325/85-20
d=41.75
w=10.88
+38.36%
|
| 335 |
335/25-20
d=26.59
w=3.30
-11.87%
|
335/30-20
d=27.91
w=3.96
-7.50%
|
335/35-20
d=29.23
w=4.62
-3.13%
|
335/40-20
d=30.55
w=5.28
+1.24%
|
335/45-20
d=31.87
w=5.94
+5.61%
|
335/50-20
d=33.19
w=6.59
+9.98%
|
335/55-20
d=34.51
w=7.25
+14.35%
|
335/60-20
d=35.83
w=7.91
+18.72%
|
335/65-20
d=37.15
w=8.57
+23.09%
|
335/70-20
d=38.46
w=9.23
+27.46%
|
335/75-20
d=39.78
w=9.89
+31.83%
|
335/80-20
d=41.10
w=10.55
+36.20%
|
335/85-20
d=42.42
w=11.21
+40.57%
|
|
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!