255/60R18 tire size
255/60R18 is a metric size: 30.0" tall, 10.0" wide, on a 18" rim — about a 30x10.00R18. The sidewall is 6.0" and the tire turns 671 times per mile.
255/60R18 specs
| Overall diameter (height) | 30.05" · 763 mm |
|---|---|
| Section width | 10.04" · 255 mm |
| Sidewall height | 6.02" · 153 mm (60% of width) |
| Rim diameter | 18" |
| Circumference | 94.40" · 2.398 m |
| Revolutions per mile | 671 (417 per km) |
| Inch (flotation) equivalent | 30x10.00R18 |
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" | -3.14% | -20 mm | 58.1 mph | compare → |
| 265/60R18 common | 30.52" | +1.57% | +10 mm | 60.9 mph | compare → |
| 225/60R18 common | 28.63" | -4.72% | -30 mm | 57.2 mph | compare → |
| 245/60R18 common | 29.57" | -1.57% | -10 mm | 59.1 mph | compare → |
| 255/55R18 common | 29.04" | -3.34% | 0 mm | 58.0 mph | compare → |
| 235/65R18 common | 30.03" | -0.07% | -20 mm | 60.0 mph | compare → |
| 255/65R18 common | 31.05" | +3.34% | 0 mm | 62.0 mph | compare → |
| 245/55R18 | 28.61" | -4.78% | -10 mm | 57.1 mph | compare → |
| 285/60R18 | 31.46" | +4.72% | +30 mm | 62.8 mph | compare → |
| 275/60R18 | 30.99" | +3.14% | +20 mm | 61.9 mph | compare → |
| 155/90R18 | 28.98" | -3.54% | -100 mm | 57.9 mph | calculate → |
| 165/90R18 | 29.69" | -1.18% | -90 mm | 59.3 mph | calculate → |
| 285/50R18 | 29.22" | -2.75% | +30 mm | 58.3 mph | calculate → |
| 305/45R18 | 28.81" | -4.13% | +50 mm | 57.5 mph | calculate → |
| 245/70R18 | 31.50" | +4.85% | -10 mm | 62.9 mph | calculate → |
| 275/55R18 | 29.91" | -0.46% | +20 mm | 59.7 mph | calculate → |
| 285/55R18 | 30.34" | +0.98% | +30 mm | 60.6 mph | calculate → |
| 175/90R18 | 30.40" | +1.18% | -80 mm | 60.7 mph | calculate → |
| 245/65R18 | 30.54" | +1.64% | -10 mm | 61.0 mph | calculate → |
| 325/45R18 | 29.52" | -1.77% | +70 mm | 58.9 mph | calculate → |
| 235/70R18 | 30.95" | +3.01% | -20 mm | 61.8 mph | calculate → |
| 225/65R18 | 29.52" | -1.77% | -30 mm | 58.9 mph | calculate → |
| 265/55R18 | 29.48" | -1.90% | +10 mm | 58.9 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 | |
|---|---|---|---|---|---|
| 255/55R19 common | 30.04" | -0.01% | 0 mm | 60.0 mph | compare → |
| 255/65R17 common | 30.05" | +0.01% | 0 mm | 60.0 mph | compare → |
| 235/70R17 | 29.95" | -0.31% | -20 mm | 59.8 mph | compare → |
| 275/50R19 | 29.83" | -0.73% | +20 mm | 59.6 mph | compare → |
| 225/75R17 | 30.29" | +0.80% | -30 mm | 60.5 mph | compare → |
| 275/60R17 | 29.99" | -0.18% | +20 mm | 59.9 mph | calculate → |
| 235/60R19 | 30.10" | +0.18% | -20 mm | 60.1 mph | calculate → |
| 175/80R19 | 30.02" | -0.08% | -80 mm | 60.0 mph | calculate → |
Try another size against 255/60R18
Questions
What size is 255/60R18 in inches?
255/60R18 is about 30.0" tall and 10.0" wide on a 18-inch rim — roughly a 30x10.00R18 in inch sizing.
What does 255/60R18 mean?
255 mm section width, sidewall 60% of the width (6.02"), radial construction, 18-inch rim.
What tire sizes are equivalent to 255/60R18?
On the same 18" rim, within 3% of the diameter: 235/65R18 (-0.07%), 275/55R18 (-0.46%), 285/55R18 (+0.98%), 165/90R18 (-1.18%), 175/90R18 (+1.18%), 245/60R18 (-1.57%).
How many revolutions per mile does a 255/60R18 tire make?
About 671 revolutions per mile (circumference 94.4").
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.