28x12.00R18 tire size
28x12.00R18 is a flotation (inch) size: 28.0" tall, 12.0" wide, on a 18" rim — about a 310/40R18. The sidewall is 5.0" and the tire turns 720 times per mile.
28x12.00R18 specs
| Overall diameter (height) | 28.00" · 711 mm |
|---|---|
| Section width | 12.00" · 305 mm |
| Sidewall height | 5.00" · 127 mm (42% of width) |
| Rim diameter | 18" |
| Circumference | 87.96" · 2.234 m |
| Revolutions per mile | 720 (448 per km) |
| Closest metric size | 310/40R18 |
Equivalent sizes on a 18" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 235/60R18 common | 29.10" | +3.94% | -70 mm | 62.4 mph | calculate → |
| 245/45R18 common | 26.68" | -4.71% | -60 mm | 57.2 mph | calculate → |
| 235/50R18 common | 27.25" | -2.67% | -70 mm | 58.4 mph | calculate → |
| 235/55R18 common | 28.18" | +0.63% | -70 mm | 60.4 mph | calculate → |
| 225/60R18 common | 28.63" | +2.25% | -80 mm | 61.3 mph | calculate → |
| 225/50R18 common | 26.86" | -4.08% | -80 mm | 57.6 mph | calculate → |
| 225/55R18 common | 27.74" | -0.91% | -80 mm | 59.5 mph | calculate → |
| 255/55R18 common | 29.04" | +3.73% | -50 mm | 62.2 mph | calculate → |
| 245/50R18 common | 27.65" | -1.27% | -60 mm | 59.2 mph | calculate → |
| 255/45R18 common | 27.04" | -3.44% | -50 mm | 57.9 mph | calculate → |
| 215/55R18 common | 27.31" | -2.46% | -90 mm | 58.5 mph | calculate → |
| 275/40R18 common | 26.66" | -4.78% | -30 mm | 57.1 mph | calculate → |
| 245/55R18 | 28.61" | +2.18% | -60 mm | 61.3 mph | calculate → |
| 275/45R18 | 27.74" | -0.91% | -30 mm | 59.5 mph | calculate → |
| 265/45R18 | 27.39" | -2.18% | -40 mm | 58.7 mph | calculate → |
| 295/40R18 | 27.29" | -2.53% | -10 mm | 58.5 mph | calculate → |
| 285/40R18 | 26.98" | -3.66% | -20 mm | 57.8 mph | calculate → |
| 345/35R18 | 27.51" | -1.76% | +40 mm | 58.9 mph | calculate → |
| 295/45R18 | 28.45" | +1.62% | -10 mm | 61.0 mph | calculate → |
| 255/50R18 | 28.04" | +0.14% | -50 mm | 60.1 mph | calculate → |
| 315/40R18 | 27.92" | -0.28% | +10 mm | 59.8 mph | calculate → |
| 155/90R18 | 28.98" | +3.52% | -150 mm | 62.1 mph | calculate → |
| 215/60R18 | 28.16" | +0.56% | -90 mm | 60.3 mph | calculate → |
| 155/85R18 | 28.37" | +1.34% | -150 mm | 60.8 mph | calculate → |
| 305/40R18 | 27.61" | -1.41% | 0 mm | 59.2 mph | calculate → |
| 305/45R18 | 28.81" | +2.88% | 0 mm | 61.7 mph | calculate → |
| 285/50R18 | 29.22" | +4.36% | -20 mm | 62.6 mph | calculate → |
| 285/45R18 | 28.10" | +0.35% | -20 mm | 60.2 mph | calculate → |
| 145/85R18 | 27.70" | -1.05% | -160 mm | 59.4 mph | calculate → |
| 145/80R18 | 27.13" | -3.09% | -160 mm | 58.1 mph | calculate → |
| 165/70R18 | 27.09" | -3.23% | -140 mm | 58.1 mph | calculate → |
| 325/35R18 | 26.96" | -3.73% | +20 mm | 57.8 mph | calculate → |
| 28x10.00R18 | 28.00" | 0.00% | -51 mm | 60.0 mph | calculate → |
| 205/60R18 | 27.69" | -1.12% | -100 mm | 59.3 mph | calculate → |
| 265/50R18 | 28.43" | +1.55% | -40 mm | 60.9 mph | calculate → |
| 195/60R18 | 27.21" | -2.81% | -110 mm | 58.3 mph | calculate → |
| 315/35R18 | 26.68" | -4.71% | +10 mm | 57.2 mph | calculate → |
Plus / minus sizing: 17" and 19" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 255/45R19 common | 28.04" | +0.13% | -50 mm | 60.1 mph | calculate → |
| 235/60R17 common | 28.10" | +0.37% | -70 mm | 60.2 mph | calculate → |
| 215/65R17 common | 28.00" | +0.01% | -90 mm | 60.0 mph | calculate → |
| 235/50R19 common | 28.25" | +0.90% | -70 mm | 60.5 mph | calculate → |
| 285/40R19 | 27.98" | -0.08% | -20 mm | 59.9 mph | calculate → |
| 155/90R17 | 27.98" | -0.06% | -150 mm | 60.0 mph | calculate → |
| 255/55R17 | 28.04" | +0.15% | -50 mm | 60.1 mph | calculate → |
| 305/45R17 | 27.81" | -0.69% | 0 mm | 59.6 mph | calculate → |
| 28x6.00R17 | 28.00" | 0.00% | -153 mm | 60.0 mph | calculate → |
| 275/50R17 | 27.83" | -0.62% | -30 mm | 59.6 mph | calculate → |
| 145/80R19 | 28.13" | +0.48% | -160 mm | 60.3 mph | calculate → |
| 345/40R17 | 27.87" | -0.48% | +40 mm | 59.7 mph | calculate → |
| 225/50R19 | 27.86" | -0.51% | -80 mm | 59.7 mph | calculate → |
Try another size against 28x12.00R18
Questions
What size is 28x12.00R18 in inches?
28x12.00R18 is about 28.0" tall and 12.0" wide on a 18-inch rim — roughly a 310/40R18 in inch sizing.
What does 28x12.00R18 mean?
28" overall diameter, 12.00" section width, radial, 18" rim.
What tire sizes are equivalent to 28x12.00R18?
On the same 18" rim, within 3% of the diameter: 28x10.00R18 (0.00%), 255/50R18 (+0.14%), 315/40R18 (-0.28%), 285/45R18 (+0.35%), 215/60R18 (+0.56%), 235/55R18 (+0.63%).
How many revolutions per mile does a 28x12.00R18 tire make?
About 720 revolutions per mile (circumference 88.0").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.