| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 295/30-21 | -0.07 % | 49.96 | 1,000.70 | 27.97 | 3.48 | 88.50 |
| 255/35-21 | +0.14 % | 50.07 | 998.59 | 28.03 | 3.51 | 89.25 |
| 195/45-21 | -0.28 % | 49.86 | 1,002.81 | 27.91 | 3.45 | 87.75 |
| 175/50-21 | -0.35 % | 49.82 | 1,003.52 | 27.89 | 3.44 | 87.50 |
| 225/40-21 | +0.35 % | 50.18 | 996.48 | 28.09 | 3.54 | 90.00 |
| 145/60-21 | -0.49 % | 49.75 | 1,004.92 | 27.85 | 3.43 | 87.00 |
| 165/55-21 | +0.56 % | 50.28 | 994.37 | 28.15 | 3.57 | 90.75 |
| 305/30-21 | +0.77 % | 50.39 | 992.26 | 28.20 | 3.60 | 91.50 |
| 215/40-21 | -0.77 % | 49.61 | 1,007.74 | 27.77 | 3.39 | 86.00 |
| 245/35-21 | -0.84 % | 49.58 | 1,008.44 | 27.75 | 3.38 | 85.75 |
| 285/30-21 | -0.91 % | 49.54 | 1,009.14 | 27.73 | 3.37 | 85.50 |
| 155/55-21 | -0.98 % | 49.51 | 1,009.85 | 27.71 | 3.36 | 85.25 |
| 205/45-21 | +0.98 % | 50.49 | 990.15 | 28.26 | 3.63 | 92.25 |
| 185/50-21 | +1.06 % | 50.53 | 989.45 | 28.28 | 3.64 | 92.50 |
| 265/35-21 | +1.13 % | 50.56 | 988.75 | 28.30 | 3.65 | 92.75 |
| 155/60-21 | +1.20 % | 50.60 | 988.04 | 28.32 | 3.66 | 93.00 |
| 335/25-21 | -1.41 % | 49.30 | 1,014.07 | 27.59 | 3.30 | 83.75 |
| 235/40-21 | +1.48 % | 50.74 | 985.23 | 28.40 | 3.70 | 94.00 |
| 185/45-21 | -1.55 % | 49.23 | 1,015.47 | 27.56 | 3.28 | 83.25 |
| 145/65-21 | +1.55 % | 50.77 | 984.53 | 28.42 | 3.71 | 94.25 |
| 315/30-21 | +1.62 % | 50.81 | 983.82 | 28.44 | 3.72 | 94.50 |
| 275/30-21 | -1.76 % | 49.12 | 1,017.58 | 27.50 | 3.25 | 82.50 |
| 165/50-21 | -1.76 % | 49.12 | 1,017.58 | 27.50 | 3.25 | 82.50 |
| 235/35-21 | -1.83 % | 49.09 | 1,018.29 | 27.48 | 3.24 | 82.25 |
| 205/40-21 | -1.90 % | 49.05 | 1,018.99 | 27.46 | 3.23 | 82.00 |
| 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
|
|||||||||||||
|
Wheel Size 21
|
|||||||||||||
| 145 |
145/25-21
d=23.85
w=1.43
-14.77%
|
145/30-21
d=24.43
w=1.71
-12.73%
|
145/35-21
d=25.00
w=2.00
-10.69%
|
145/40-21
d=25.57
w=2.28
-8.65%
|
145/45-21
d=26.14
w=2.57
-6.61%
|
145/50-21
d=26.71
w=2.85
-4.57%
|
145/55-21
d=27.28
w=3.14
-2.53%
|
145/60-21
d=27.85
w=3.43
-0.49%
|
145/65-21
d=28.42
w=3.71
+1.55%
|
145/70-21
d=28.99
w=4.00
+3.59%
|
145/75-21
d=29.56
w=4.28
+5.63%
|
145/80-21
d=30.13
w=4.57
+7.67%
|
145/85-21
d=30.70
w=4.85
+9.71%
|
| 155 |
155/25-21
d=24.05
w=1.53
-14.07%
|
155/30-21
d=24.66
w=1.83
-11.89%
|
155/35-21
d=25.27
w=2.14
-9.71%
|
155/40-21
d=25.88
w=2.44
-7.53%
|
155/45-21
d=26.49
w=2.75
-5.35%
|
155/50-21
d=27.10
w=3.05
-3.17%
|
155/55-21
d=27.71
w=3.36
-0.98%
|
155/60-21
d=28.32
w=3.66
+1.20%
|
155/65-21
d=28.93
w=3.97
+3.38%
|
155/70-21
d=29.54
w=4.27
+5.56%
|
155/75-21
d=30.15
w=4.58
+7.74%
|
155/80-21
d=30.76
w=4.88
+9.92%
|
155/85-21
d=31.37
w=5.19
+12.10%
|
| 165 |
165/25-21
d=24.25
w=1.62
-13.36%
|
165/30-21
d=24.90
w=1.95
-11.04%
|
165/35-21
d=25.55
w=2.27
-8.72%
|
165/40-21
d=26.20
w=2.60
-6.40%
|
165/45-21
d=26.85
w=2.92
-4.08%
|
165/50-21
d=27.50
w=3.25
-1.76%
|
165/55-21
d=28.15
w=3.57
+0.56%
|
165/60-21
d=28.80
w=3.90
+2.88%
|
165/65-21
d=29.44
w=4.22
+5.20%
|
165/70-21
d=30.09
w=4.55
+7.53%
|
165/75-21
d=30.74
w=4.87
+9.85%
|
165/80-21
d=31.39
w=5.20
+12.17%
|
165/85-21
d=32.04
w=5.52
+14.49%
|
| 175 |
175/25-21
d=24.44
w=1.72
-12.66%
|
175/30-21
d=25.13
w=2.07
-10.20%
|
175/35-21
d=25.82
w=2.41
-7.74%
|
175/40-21
d=26.51
w=2.76
-5.28%
|
175/45-21
d=27.20
w=3.10
-2.81%
|
175/50-21
d=27.89
w=3.44
-0.35%
|
175/55-21
d=28.58
w=3.79
+2.11%
|
175/60-21
d=29.27
w=4.13
+4.57%
|
175/65-21
d=29.96
w=4.48
+7.03%
|
175/70-21
d=30.65
w=4.82
+9.50%
|
175/75-21
d=31.33
w=5.17
+11.96%
|
175/80-21
d=32.02
w=5.51
+14.42%
|
175/85-21
d=32.71
w=5.86
+16.88%
|
| 185 |
185/25-21
d=24.64
w=1.82
-11.96%
|
185/30-21
d=25.37
w=2.19
-9.35%
|
185/35-21
d=26.10
w=2.55
-6.75%
|
185/40-21
d=26.83
w=2.91
-4.15%
|
185/45-21
d=27.56
w=3.28
-1.55%
|
185/50-21
d=28.28
w=3.64
+1.06%
|
185/55-21
d=29.01
w=4.01
+3.66%
|
185/60-21
d=29.74
w=4.37
+6.26%
|
185/65-21
d=30.47
w=4.73
+8.86%
|
185/70-21
d=31.20
w=5.10
+11.46%
|
185/75-21
d=31.93
w=5.46
+14.07%
|
185/80-21
d=32.65
w=5.83
+16.67%
|
185/85-21
d=33.38
w=6.19
+19.27%
|
| 195 |
195/25-21
d=24.84
w=1.92
-11.25%
|
195/30-21
d=25.61
w=2.30
-8.51%
|
195/35-21
d=26.37
w=2.69
-5.77%
|
195/40-21
d=27.14
w=3.07
-3.02%
|
195/45-21
d=27.91
w=3.45
-0.28%
|
195/50-21
d=28.68
w=3.84
+2.46%
|
195/55-21
d=29.44
w=4.22
+5.20%
|
195/60-21
d=30.21
w=4.61
+7.95%
|
195/65-21
d=30.98
w=4.99
+10.69%
|
195/70-21
d=31.75
w=5.37
+13.43%
|
195/75-21
d=32.52
w=5.76
+16.18%
|
195/80-21
d=33.28
w=6.14
+18.92%
|
195/85-21
d=34.05
w=6.53
+21.66%
|
| 205 |
205/25-21
d=25.04
w=2.02
-10.55%
|
205/30-21
d=25.84
w=2.42
-7.67%
|
205/35-21
d=26.65
w=2.82
-4.78%
|
205/40-21
d=27.46
w=3.23
-1.90%
|
205/45-21
d=28.26
w=3.63
+0.98%
|
205/50-21
d=29.07
w=4.04
+3.87%
|
205/55-21
d=29.88
w=4.44
+6.75%
|
205/60-21
d=30.69
w=4.84
+9.64%
|
205/65-21
d=31.49
w=5.25
+12.52%
|
205/70-21
d=32.30
w=5.65
+15.40%
|
205/75-21
d=33.11
w=6.05
+18.29%
|
205/80-21
d=33.91
w=6.46
+21.17%
|
205/85-21
d=34.72
w=6.86
+24.05%
|
| 215 |
215/25-21
d=25.23
w=2.12
-9.85%
|
215/30-21
d=26.08
w=2.54
-6.82%
|
215/35-21
d=26.93
w=2.96
-3.80%
|
215/40-21
d=27.77
w=3.39
-0.77%
|
215/45-21
d=28.62
w=3.81
+2.25%
|
215/50-21
d=29.46
w=4.23
+5.28%
|
215/55-21
d=30.31
w=4.66
+8.30%
|
215/60-21
d=31.16
w=5.08
+11.32%
|
215/65-21
d=32.00
w=5.50
+14.35%
|
215/70-21
d=32.85
w=5.93
+17.37%
|
215/75-21
d=33.70
w=6.35
+20.40%
|
215/80-21
d=34.54
w=6.77
+23.42%
|
215/85-21
d=35.39
w=7.19
+26.45%
|
| 225 |
225/25-21
d=25.43
w=2.21
-9.14%
|
225/30-21
d=26.31
w=2.66
-5.98%
|
225/35-21
d=27.20
w=3.10
-2.81%
|
225/40-21
d=28.09
w=3.54
+0.35%
|
225/45-21
d=28.97
w=3.99
+3.52%
|
225/50-21
d=29.86
w=4.43
+6.68%
|
225/55-21
d=30.74
w=4.87
+9.85%
|
225/60-21
d=31.63
w=5.31
+13.01%
|
225/65-21
d=32.52
w=5.76
+16.18%
|
225/70-21
d=33.40
w=6.20
+19.34%
|
225/75-21
d=34.29
w=6.64
+22.51%
|
225/80-21
d=35.17
w=7.09
+25.67%
|
225/85-21
d=36.06
w=7.53
+28.84%
|
| 235 |
235/25-21
d=25.63
w=2.31
-8.44%
|
235/30-21
d=26.55
w=2.78
-5.13%
|
235/35-21
d=27.48
w=3.24
-1.83%
|
235/40-21
d=28.40
w=3.70
+1.48%
|
235/45-21
d=29.33
w=4.16
+4.78%
|
235/50-21
d=30.25
w=4.63
+8.09%
|
235/55-21
d=31.18
w=5.09
+11.39%
|
235/60-21
d=32.10
w=5.55
+14.70%
|
235/65-21
d=33.03
w=6.01
+18.01%
|
235/70-21
d=33.95
w=6.48
+21.31%
|
235/75-21
d=34.88
w=6.94
+24.62%
|
235/80-21
d=35.80
w=7.40
+27.92%
|
235/85-21
d=36.73
w=7.86
+31.23%
|
| 245 |
245/25-21
d=25.82
w=2.41
-7.74%
|
245/30-21
d=26.79
w=2.89
-4.29%
|
245/35-21
d=27.75
w=3.38
-0.84%
|
245/40-21
d=28.72
w=3.86
+2.60%
|
245/45-21
d=29.68
w=4.34
+6.05%
|
245/50-21
d=30.65
w=4.82
+9.50%
|
245/55-21
d=31.61
w=5.31
+12.94%
|
245/60-21
d=32.57
w=5.79
+16.39%
|
245/65-21
d=33.54
w=6.27
+19.83%
|
245/70-21
d=34.50
w=6.75
+23.28%
|
245/75-21
d=35.47
w=7.23
+26.73%
|
245/80-21
d=36.43
w=7.72
+30.17%
|
245/85-21
d=37.40
w=8.20
+33.62%
|
| 255 |
255/25-21
d=26.02
w=2.51
-7.03%
|
255/30-21
d=27.02
w=3.01
-3.45%
|
255/35-21
d=28.03
w=3.51
+0.14%
|
255/40-21
d=29.03
w=4.02
+3.73%
|
255/45-21
d=30.04
w=4.52
+7.31%
|
255/50-21
d=31.04
w=5.02
+10.90%
|
255/55-21
d=32.04
w=5.52
+14.49%
|
255/60-21
d=33.05
w=6.02
+18.08%
|
255/65-21
d=34.05
w=6.53
+21.66%
|
255/70-21
d=35.06
w=7.03
+25.25%
|
255/75-21
d=36.06
w=7.53
+28.84%
|
255/80-21
d=37.06
w=8.03
+32.42%
|
255/85-21
d=38.07
w=8.53
+36.01%
|
| 265 |
265/25-21
d=26.22
w=2.61
-6.33%
|
265/30-21
d=27.26
w=3.13
-2.60%
|
265/35-21
d=28.30
w=3.65
+1.13%
|
265/40-21
d=29.35
w=4.17
+4.85%
|
265/45-21
d=30.39
w=4.69
+8.58%
|
265/50-21
d=31.43
w=5.22
+12.31%
|
265/55-21
d=32.48
w=5.74
+16.04%
|
265/60-21
d=33.52
w=6.26
+19.76%
|
265/65-21
d=34.56
w=6.78
+23.49%
|
265/70-21
d=35.61
w=7.30
+27.22%
|
265/75-21
d=36.65
w=7.82
+30.95%
|
265/80-21
d=37.69
w=8.35
+34.67%
|
265/85-21
d=38.74
w=8.87
+38.40%
|
| 275 |
275/25-21
d=26.41
w=2.71
-5.63%
|
275/30-21
d=27.50
w=3.25
-1.76%
|
275/35-21
d=28.58
w=3.79
+2.11%
|
275/40-21
d=29.66
w=4.33
+5.98%
|
275/45-21
d=30.74
w=4.87
+9.85%
|
275/50-21
d=31.83
w=5.41
+13.72%
|
275/55-21
d=32.91
w=5.95
+17.58%
|
275/60-21
d=33.99
w=6.50
+21.45%
|
275/65-21
d=35.07
w=7.04
+25.32%
|
275/70-21
d=36.16
w=7.58
+29.19%
|
275/75-21
d=37.24
w=8.12
+33.06%
|
275/80-21
d=38.32
w=8.66
+36.93%
|
275/85-21
d=39.41
w=9.20
+40.79%
|
| 285 |
285/25-21
d=26.61
w=2.81
-4.92%
|
285/30-21
d=27.73
w=3.37
-0.91%
|
285/35-21
d=28.85
w=3.93
+3.09%
|
285/40-21
d=29.98
w=4.49
+7.10%
|
285/45-21
d=31.10
w=5.05
+11.11%
|
285/50-21
d=32.22
w=5.61
+15.12%
|
285/55-21
d=33.34
w=6.17
+19.13%
|
285/60-21
d=34.46
w=6.73
+23.14%
|
285/65-21
d=35.59
w=7.29
+27.15%
|
285/70-21
d=36.71
w=7.85
+31.16%
|
285/75-21
d=37.83
w=8.42
+35.17%
|
285/80-21
d=38.95
w=8.98
+39.18%
|
285/85-21
d=40.07
w=9.54
+43.18%
|
| 295 |
295/25-21
d=26.81
w=2.90
-4.22%
|
295/30-21
d=27.97
w=3.48
-0.07%
|
295/35-21
d=29.13
w=4.06
+4.08%
|
295/40-21
d=30.29
w=4.65
+8.23%
|
295/45-21
d=31.45
w=5.23
+12.38%
|
295/50-21
d=32.61
w=5.81
+16.53%
|
295/55-21
d=33.78
w=6.39
+20.68%
|
295/60-21
d=34.94
w=6.97
+24.83%
|
295/65-21
d=36.10
w=7.55
+28.98%
|
295/70-21
d=37.26
w=8.13
+33.13%
|
295/75-21
d=38.42
w=8.71
+37.28%
|
295/80-21
d=39.58
w=9.29
+41.43%
|
295/85-21
d=40.74
w=9.87
+45.58%
|
| 305 |
305/25-21
d=27.00
w=3.00
-3.52%
|
305/30-21
d=28.20
w=3.60
+0.77%
|
305/35-21
d=29.41
w=4.20
+5.06%
|
305/40-21
d=30.61
w=4.80
+9.35%
|
305/45-21
d=31.81
w=5.40
+13.64%
|
305/50-21
d=33.01
w=6.00
+17.94%
|
305/55-21
d=34.21
w=6.60
+22.23%
|
305/60-21
d=35.41
w=7.20
+26.52%
|
305/65-21
d=36.61
w=7.81
+30.81%
|
305/70-21
d=37.81
w=8.41
+35.10%
|
305/75-21
d=39.01
w=9.01
+39.39%
|
305/80-21
d=40.21
w=9.61
+43.68%
|
305/85-21
d=41.41
w=10.21
+47.97%
|
| 315 |
315/25-21
d=27.20
w=3.10
-2.81%
|
315/30-21
d=28.44
w=3.72
+1.62%
|
315/35-21
d=29.68
w=4.34
+6.05%
|
315/40-21
d=30.92
w=4.96
+10.48%
|
315/45-21
d=32.16
w=5.58
+14.91%
|
315/50-21
d=33.40
w=6.20
+19.34%
|
315/55-21
d=34.64
w=6.82
+23.77%
|
315/60-21
d=35.88
w=7.44
+28.20%
|
315/65-21
d=37.12
w=8.06
+32.63%
|
315/70-21
d=38.36
w=8.68
+37.07%
|
315/75-21
d=39.60
w=9.30
+41.50%
|
315/80-21
d=40.84
w=9.92
+45.93%
|
315/85-21
d=42.08
w=10.54
+50.36%
|
| 325 |
325/25-21
d=27.40
w=3.20
-2.11%
|
325/30-21
d=28.68
w=3.84
+2.46%
|
325/35-21
d=29.96
w=4.48
+7.03%
|
325/40-21
d=31.24
w=5.12
+11.61%
|
325/45-21
d=32.52
w=5.76
+16.18%
|
325/50-21
d=33.80
w=6.40
+20.75%
|
325/55-21
d=35.07
w=7.04
+25.32%
|
325/60-21
d=36.35
w=7.68
+29.89%
|
325/65-21
d=37.63
w=8.32
+34.46%
|
325/70-21
d=38.91
w=8.96
+39.04%
|
325/75-21
d=40.19
w=9.60
+43.61%
|
325/80-21
d=41.47
w=10.24
+48.18%
|
325/85-21
d=42.75
w=10.88
+52.75%
|
| 335 |
335/25-21
d=27.59
w=3.30
-1.41%
|
335/30-21
d=28.91
w=3.96
+3.31%
|
335/35-21
d=30.23
w=4.62
+8.02%
|
335/40-21
d=31.55
w=5.28
+12.73%
|
335/45-21
d=32.87
w=5.94
+17.44%
|
335/50-21
d=34.19
w=6.59
+22.16%
|
335/55-21
d=35.51
w=7.25
+26.87%
|
335/60-21
d=36.83
w=7.91
+31.58%
|
335/65-21
d=38.15
w=8.57
+36.29%
|
335/70-21
d=39.46
w=9.23
+41.00%
|
335/75-21
d=40.78
w=9.89
+45.72%
|
335/80-21
d=42.10
w=10.55
+50.43%
|
335/85-21
d=43.42
w=11.21
+55.14%
|
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!