| Code | Difference | = 50mph | 1000miles = | Diameter | Wall,in | Wall,mm |
|---|---|---|---|---|---|---|
| 245/85-21 | -0.12 % | 49.94 | 1,001.16 | 37.40 | 8.20 | 208.25 |
| 295/70-21 | -0.48 % | 49.76 | 1,004.84 | 37.26 | 8.13 | 206.50 |
| 325/65-21 | +0.52 % | 50.26 | 994.85 | 37.63 | 8.32 | 211.25 |
| 275/75-21 | -0.54 % | 49.73 | 1,005.36 | 37.24 | 8.12 | 206.25 |
| 265/80-21 | +0.67 % | 50.34 | 993.27 | 37.69 | 8.35 | 212.00 |
| 315/65-21 | -0.85 % | 49.57 | 1,008.52 | 37.12 | 8.06 | 204.75 |
| 305/70-21 | +0.99 % | 50.49 | 990.12 | 37.81 | 8.41 | 213.50 |
| 255/80-21 | -1.01 % | 49.50 | 1,010.09 | 37.06 | 8.03 | 204.00 |
| 285/75-21 | +1.04 % | 50.52 | 989.59 | 37.83 | 8.42 | 213.75 |
| 335/60-21 | -1.64 % | 49.18 | 1,016.40 | 36.83 | 7.91 | 201.00 |
| 255/85-21 | +1.67 % | 50.84 | 983.28 | 38.07 | 8.53 | 216.75 |
| 335/65-21 | +1.88 % | 50.94 | 981.18 | 38.15 | 8.57 | 217.75 |
| 235/85-21 | -1.90 % | 49.05 | 1,019.03 | 36.73 | 7.86 | 199.75 |
| 285/70-21 | -1.96 % | 49.02 | 1,019.56 | 36.71 | 7.85 | 199.50 |
| 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
|
|||||||||||||
|
Wheel Size 19
|
|||||||||||||
|
Wheel Size 20
|
|||||||||||||
|
Wheel Size 21
|
|||||||||||||
| 145 |
145/25-21
d=23.85
w=1.43
-36.29%
|
145/30-21
d=24.43
w=1.71
-34.76%
|
145/35-21
d=25.00
w=2.00
-33.24%
|
145/40-21
d=25.57
w=2.28
-31.71%
|
145/45-21
d=26.14
w=2.57
-30.19%
|
145/50-21
d=26.71
w=2.85
-28.66%
|
145/55-21
d=27.28
w=3.14
-27.14%
|
145/60-21
d=27.85
w=3.43
-25.62%
|
145/65-21
d=28.42
w=3.71
-24.09%
|
145/70-21
d=28.99
w=4.00
-22.57%
|
145/75-21
d=29.56
w=4.28
-21.04%
|
145/80-21
d=30.13
w=4.57
-19.52%
|
145/85-21
d=30.70
w=4.85
-17.99%
|
| 155 |
155/25-21
d=24.05
w=1.53
-35.76%
|
155/30-21
d=24.66
w=1.83
-34.13%
|
155/35-21
d=25.27
w=2.14
-32.50%
|
155/40-21
d=25.88
w=2.44
-30.87%
|
155/45-21
d=26.49
w=2.75
-29.24%
|
155/50-21
d=27.10
w=3.05
-27.61%
|
155/55-21
d=27.71
w=3.36
-25.98%
|
155/60-21
d=28.32
w=3.66
-24.35%
|
155/65-21
d=28.93
w=3.97
-22.72%
|
155/70-21
d=29.54
w=4.27
-21.09%
|
155/75-21
d=30.15
w=4.58
-19.46%
|
155/80-21
d=30.76
w=4.88
-17.83%
|
155/85-21
d=31.37
w=5.19
-16.20%
|
| 165 |
165/25-21
d=24.25
w=1.62
-35.24%
|
165/30-21
d=24.90
w=1.95
-33.50%
|
165/35-21
d=25.55
w=2.27
-31.77%
|
165/40-21
d=26.20
w=2.60
-30.03%
|
165/45-21
d=26.85
w=2.92
-28.30%
|
165/50-21
d=27.50
w=3.25
-26.56%
|
165/55-21
d=28.15
w=3.57
-24.83%
|
165/60-21
d=28.80
w=3.90
-23.09%
|
165/65-21
d=29.44
w=4.22
-21.36%
|
165/70-21
d=30.09
w=4.55
-19.62%
|
165/75-21
d=30.74
w=4.87
-17.89%
|
165/80-21
d=31.39
w=5.20
-16.15%
|
165/85-21
d=32.04
w=5.52
-14.42%
|
| 175 |
175/25-21
d=24.44
w=1.72
-34.71%
|
175/30-21
d=25.13
w=2.07
-32.87%
|
175/35-21
d=25.82
w=2.41
-31.03%
|
175/40-21
d=26.51
w=2.76
-29.19%
|
175/45-21
d=27.20
w=3.10
-27.35%
|
175/50-21
d=27.89
w=3.44
-25.51%
|
175/55-21
d=28.58
w=3.79
-23.67%
|
175/60-21
d=29.27
w=4.13
-21.83%
|
175/65-21
d=29.96
w=4.48
-19.99%
|
175/70-21
d=30.65
w=4.82
-18.15%
|
175/75-21
d=31.33
w=5.17
-16.31%
|
175/80-21
d=32.02
w=5.51
-14.47%
|
175/85-21
d=32.71
w=5.86
-12.63%
|
| 185 |
185/25-21
d=24.64
w=1.82
-34.19%
|
185/30-21
d=25.37
w=2.19
-32.24%
|
185/35-21
d=26.10
w=2.55
-30.29%
|
185/40-21
d=26.83
w=2.91
-28.35%
|
185/45-21
d=27.56
w=3.28
-26.40%
|
185/50-21
d=28.28
w=3.64
-24.46%
|
185/55-21
d=29.01
w=4.01
-22.51%
|
185/60-21
d=29.74
w=4.37
-20.57%
|
185/65-21
d=30.47
w=4.73
-18.62%
|
185/70-21
d=31.20
w=5.10
-16.68%
|
185/75-21
d=31.93
w=5.46
-14.73%
|
185/80-21
d=32.65
w=5.83
-12.79%
|
185/85-21
d=33.38
w=6.19
-10.84%
|
| 195 |
195/25-21
d=24.84
w=1.92
-33.66%
|
195/30-21
d=25.61
w=2.30
-31.61%
|
195/35-21
d=26.37
w=2.69
-29.56%
|
195/40-21
d=27.14
w=3.07
-27.51%
|
195/45-21
d=27.91
w=3.45
-25.46%
|
195/50-21
d=28.68
w=3.84
-23.41%
|
195/55-21
d=29.44
w=4.22
-21.36%
|
195/60-21
d=30.21
w=4.61
-19.31%
|
195/65-21
d=30.98
w=4.99
-17.26%
|
195/70-21
d=31.75
w=5.37
-15.21%
|
195/75-21
d=32.52
w=5.76
-13.15%
|
195/80-21
d=33.28
w=6.14
-11.10%
|
195/85-21
d=34.05
w=6.53
-9.05%
|
| 205 |
205/25-21
d=25.04
w=2.02
-33.13%
|
205/30-21
d=25.84
w=2.42
-30.98%
|
205/35-21
d=26.65
w=2.82
-28.82%
|
205/40-21
d=27.46
w=3.23
-26.67%
|
205/45-21
d=28.26
w=3.63
-24.51%
|
205/50-21
d=29.07
w=4.04
-22.36%
|
205/55-21
d=29.88
w=4.44
-20.20%
|
205/60-21
d=30.69
w=4.84
-18.04%
|
205/65-21
d=31.49
w=5.25
-15.89%
|
205/70-21
d=32.30
w=5.65
-13.73%
|
205/75-21
d=33.11
w=6.05
-11.58%
|
205/80-21
d=33.91
w=6.46
-9.42%
|
205/85-21
d=34.72
w=6.86
-7.27%
|
| 215 |
215/25-21
d=25.23
w=2.12
-32.61%
|
215/30-21
d=26.08
w=2.54
-30.35%
|
215/35-21
d=26.93
w=2.96
-28.09%
|
215/40-21
d=27.77
w=3.39
-25.83%
|
215/45-21
d=28.62
w=3.81
-23.56%
|
215/50-21
d=29.46
w=4.23
-21.30%
|
215/55-21
d=30.31
w=4.66
-19.04%
|
215/60-21
d=31.16
w=5.08
-16.78%
|
215/65-21
d=32.00
w=5.50
-14.52%
|
215/70-21
d=32.85
w=5.93
-12.26%
|
215/75-21
d=33.70
w=6.35
-10.00%
|
215/80-21
d=34.54
w=6.77
-7.74%
|
215/85-21
d=35.39
w=7.19
-5.48%
|
| 225 |
225/25-21
d=25.43
w=2.21
-32.08%
|
225/30-21
d=26.31
w=2.66
-29.72%
|
225/35-21
d=27.20
w=3.10
-27.35%
|
225/40-21
d=28.09
w=3.54
-24.98%
|
225/45-21
d=28.97
w=3.99
-22.62%
|
225/50-21
d=29.86
w=4.43
-20.25%
|
225/55-21
d=30.74
w=4.87
-17.89%
|
225/60-21
d=31.63
w=5.31
-15.52%
|
225/65-21
d=32.52
w=5.76
-13.15%
|
225/70-21
d=33.40
w=6.20
-10.79%
|
225/75-21
d=34.29
w=6.64
-8.42%
|
225/80-21
d=35.17
w=7.09
-6.06%
|
225/85-21
d=36.06
w=7.53
-3.69%
|
| 235 |
235/25-21
d=25.63
w=2.31
-31.56%
|
235/30-21
d=26.55
w=2.78
-29.09%
|
235/35-21
d=27.48
w=3.24
-26.61%
|
235/40-21
d=28.40
w=3.70
-24.14%
|
235/45-21
d=29.33
w=4.16
-21.67%
|
235/50-21
d=30.25
w=4.63
-19.20%
|
235/55-21
d=31.18
w=5.09
-16.73%
|
235/60-21
d=32.10
w=5.55
-14.26%
|
235/65-21
d=33.03
w=6.01
-11.79%
|
235/70-21
d=33.95
w=6.48
-9.32%
|
235/75-21
d=34.88
w=6.94
-6.85%
|
235/80-21
d=35.80
w=7.40
-4.37%
|
235/85-21
d=36.73
w=7.86
-1.90%
|
| 245 |
245/25-21
d=25.82
w=2.41
-31.03%
|
245/30-21
d=26.79
w=2.89
-28.45%
|
245/35-21
d=27.75
w=3.38
-25.88%
|
245/40-21
d=28.72
w=3.86
-23.30%
|
245/45-21
d=29.68
w=4.34
-20.73%
|
245/50-21
d=30.65
w=4.82
-18.15%
|
245/55-21
d=31.61
w=5.31
-15.57%
|
245/60-21
d=32.57
w=5.79
-13.00%
|
245/65-21
d=33.54
w=6.27
-10.42%
|
245/70-21
d=34.50
w=6.75
-7.84%
|
245/75-21
d=35.47
w=7.23
-5.27%
|
245/80-21
d=36.43
w=7.72
-2.69%
|
245/85-21
d=37.40
w=8.20
-0.12%
|
| 255 |
255/25-21
d=26.02
w=2.51
-30.50%
|
255/30-21
d=27.02
w=3.01
-27.82%
|
255/35-21
d=28.03
w=3.51
-25.14%
|
255/40-21
d=29.03
w=4.02
-22.46%
|
255/45-21
d=30.04
w=4.52
-19.78%
|
255/50-21
d=31.04
w=5.02
-17.10%
|
255/55-21
d=32.04
w=5.52
-14.42%
|
255/60-21
d=33.05
w=6.02
-11.74%
|
255/65-21
d=34.05
w=6.53
-9.05%
|
255/70-21
d=35.06
w=7.03
-6.37%
|
255/75-21
d=36.06
w=7.53
-3.69%
|
255/80-21
d=37.06
w=8.03
-1.01%
|
255/85-21
d=38.07
w=8.53
+1.67%
|
| 265 |
265/25-21
d=26.22
w=2.61
-29.98%
|
265/30-21
d=27.26
w=3.13
-27.19%
|
265/35-21
d=28.30
w=3.65
-24.41%
|
265/40-21
d=29.35
w=4.17
-21.62%
|
265/45-21
d=30.39
w=4.69
-18.83%
|
265/50-21
d=31.43
w=5.22
-16.05%
|
265/55-21
d=32.48
w=5.74
-13.26%
|
265/60-21
d=33.52
w=6.26
-10.47%
|
265/65-21
d=34.56
w=6.78
-7.69%
|
265/70-21
d=35.61
w=7.30
-4.90%
|
265/75-21
d=36.65
w=7.82
-2.11%
|
265/80-21
d=37.69
w=8.35
+0.67%
|
265/85-21
d=38.74
w=8.87
+3.46%
|
| 275 |
275/25-21
d=26.41
w=2.71
-29.45%
|
275/30-21
d=27.50
w=3.25
-26.56%
|
275/35-21
d=28.58
w=3.79
-23.67%
|
275/40-21
d=29.66
w=4.33
-20.78%
|
275/45-21
d=30.74
w=4.87
-17.89%
|
275/50-21
d=31.83
w=5.41
-14.99%
|
275/55-21
d=32.91
w=5.95
-12.10%
|
275/60-21
d=33.99
w=6.50
-9.21%
|
275/65-21
d=35.07
w=7.04
-6.32%
|
275/70-21
d=36.16
w=7.58
-3.43%
|
275/75-21
d=37.24
w=8.12
-0.54%
|
275/80-21
d=38.32
w=8.66
+2.36%
|
275/85-21
d=39.41
w=9.20
+5.25%
|
| 285 |
285/25-21
d=26.61
w=2.81
-28.93%
|
285/30-21
d=27.73
w=3.37
-25.93%
|
285/35-21
d=28.85
w=3.93
-22.93%
|
285/40-21
d=29.98
w=4.49
-19.94%
|
285/45-21
d=31.10
w=5.05
-16.94%
|
285/50-21
d=32.22
w=5.61
-13.94%
|
285/55-21
d=33.34
w=6.17
-10.95%
|
285/60-21
d=34.46
w=6.73
-7.95%
|
285/65-21
d=35.59
w=7.29
-4.95%
|
285/70-21
d=36.71
w=7.85
-1.96%
|
285/75-21
d=37.83
w=8.42
+1.04%
|
285/80-21
d=38.95
w=8.98
+4.04%
|
285/85-21
d=40.07
w=9.54
+7.03%
|
| 295 |
295/25-21
d=26.81
w=2.90
-28.40%
|
295/30-21
d=27.97
w=3.48
-25.30%
|
295/35-21
d=29.13
w=4.06
-22.20%
|
295/40-21
d=30.29
w=4.65
-19.10%
|
295/45-21
d=31.45
w=5.23
-15.99%
|
295/50-21
d=32.61
w=5.81
-12.89%
|
295/55-21
d=33.78
w=6.39
-9.79%
|
295/60-21
d=34.94
w=6.97
-6.69%
|
295/65-21
d=36.10
w=7.55
-3.59%
|
295/70-21
d=37.26
w=8.13
-0.48%
|
295/75-21
d=38.42
w=8.71
+2.62%
|
295/80-21
d=39.58
w=9.29
+5.72%
|
295/85-21
d=40.74
w=9.87
+8.82%
|
| 305 |
305/25-21
d=27.00
w=3.00
-27.88%
|
305/30-21
d=28.20
w=3.60
-24.67%
|
305/35-21
d=29.41
w=4.20
-21.46%
|
305/40-21
d=30.61
w=4.80
-18.25%
|
305/45-21
d=31.81
w=5.40
-15.05%
|
305/50-21
d=33.01
w=6.00
-11.84%
|
305/55-21
d=34.21
w=6.60
-8.63%
|
305/60-21
d=35.41
w=7.20
-5.43%
|
305/65-21
d=36.61
w=7.81
-2.22%
|
305/70-21
d=37.81
w=8.41
+0.99%
|
305/75-21
d=39.01
w=9.01
+4.20%
|
305/80-21
d=40.21
w=9.61
+7.40%
|
305/85-21
d=41.41
w=10.21
+10.61%
|
| 315 |
315/25-21
d=27.20
w=3.10
-27.35%
|
315/30-21
d=28.44
w=3.72
-24.04%
|
315/35-21
d=29.68
w=4.34
-20.73%
|
315/40-21
d=30.92
w=4.96
-17.41%
|
315/45-21
d=32.16
w=5.58
-14.10%
|
315/50-21
d=33.40
w=6.20
-10.79%
|
315/55-21
d=34.64
w=6.82
-7.48%
|
315/60-21
d=35.88
w=7.44
-4.16%
|
315/65-21
d=37.12
w=8.06
-0.85%
|
315/70-21
d=38.36
w=8.68
+2.46%
|
315/75-21
d=39.60
w=9.30
+5.77%
|
315/80-21
d=40.84
w=9.92
+9.09%
|
315/85-21
d=42.08
w=10.54
+12.40%
|
| 325 |
325/25-21
d=27.40
w=3.20
-26.82%
|
325/30-21
d=28.68
w=3.84
-23.41%
|
325/35-21
d=29.96
w=4.48
-19.99%
|
325/40-21
d=31.24
w=5.12
-16.57%
|
325/45-21
d=32.52
w=5.76
-13.15%
|
325/50-21
d=33.80
w=6.40
-9.74%
|
325/55-21
d=35.07
w=7.04
-6.32%
|
325/60-21
d=36.35
w=7.68
-2.90%
|
325/65-21
d=37.63
w=8.32
+0.52%
|
325/70-21
d=38.91
w=8.96
+3.93%
|
325/75-21
d=40.19
w=9.60
+7.35%
|
325/80-21
d=41.47
w=10.24
+10.77%
|
325/85-21
d=42.75
w=10.88
+14.19%
|
| 335 |
335/25-21
d=27.59
w=3.30
-26.30%
|
335/30-21
d=28.91
w=3.96
-22.78%
|
335/35-21
d=30.23
w=4.62
-19.25%
|
335/40-21
d=31.55
w=5.28
-15.73%
|
335/45-21
d=32.87
w=5.94
-12.21%
|
335/50-21
d=34.19
w=6.59
-8.69%
|
335/55-21
d=35.51
w=7.25
-5.16%
|
335/60-21
d=36.83
w=7.91
-1.64%
|
335/65-21
d=38.15
w=8.57
+1.88%
|
335/70-21
d=39.46
w=9.23
+5.40%
|
335/75-21
d=40.78
w=9.89
+8.93%
|
335/80-21
d=42.10
w=10.55
+12.45%
|
335/85-21
d=43.42
w=11.21
+15.97%
|
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!