255/75R18 tire size in inches
A 255/75R18 tire measures
33.1" tall × 10.0" wide
7.53" sidewall on a 18" wheel. 610 revolutions per mile.
255/75R18 means a tire 255 mm wide, with sidewalls 75% as tall as the tire is wide (191 mm), radial construction (R), for a 18 inch wheel.
255/75R18 specs
| Overall diameter (height) | 33.06 inches (840 mm) |
|---|---|
| Section width | 10.04 inches (255 mm) |
| Sidewall height | 7.53 inches (191 mm) |
| Wheel (rim) diameter | 18 inches |
| Circumference | 103.9 inches (2,638 mm) |
| Revolutions per mile | 610 |
| Revolutions per kilometer | 379 |
| Approximate rim width | 7.0" to 8.5" |
| In inches (flotation style) | 33.1x10.0R18 |
| Aspect ratio | 75% |
Calculated from the size. Real tires differ by brand, model and tread depth, typically by a few tenths of an inch.
Sizes that can replace 255/75R18 on a 18" wheel
These 18" sizes are within 3% of 255/75R18's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 295/65R18 | 33.10" | 11.61" | +0.1% | 60.1 mph | Compare |
| 33x12.50R18 | 33.00" | 12.50" | −0.2% | 59.9 mph | Compare |
| 275/70R18 | 33.16" | 10.83" | +0.3% | 60.2 mph | Compare |
| 315/60R18 | 32.88" | 12.40" | −0.5% | 59.7 mph | Compare |
| 325/60R18 | 33.35" | 12.80" | +0.9% | 60.5 mph | Compare |
| 265/70R18 | 32.61" | 10.43" | −1.4% | 59.2 mph | Compare |
| 285/65R18 | 32.59" | 11.22" | −1.4% | 59.1 mph | Compare |
| 305/65R18 | 33.61" | 12.01" | +1.7% | 61.0 mph | Compare |
| 335/55R18 | 32.51" | 13.19" | −1.7% | 59.0 mph | Compare |
| 245/75R18 | 32.47" | 9.65" | −1.8% | 58.9 mph | Compare |
| 265/75R18 | 33.65" | 10.43" | +1.8% | 61.1 mph | Compare |
| 285/70R18 | 33.71" | 11.22" | +2.0% | 61.2 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 255/85R16 | 16" | 33.07" | 0.0% | Compare |
| 255/65R20 | 20" | 33.05" | 0.0% | Compare |
| 255/55R22 | 22" | 33.04" | 0.0% | Compare |
| 275/65R19 | 19" | 33.07" | 0.0% | Compare |
| 325/55R19 | 19" | 33.07" | 0.0% | Compare |
| 305/50R21 | 21" | 33.01" | −0.2% | Compare |
| 33x12.50R15 | 15" | 33.00" | −0.2% | Compare |
| 33x12.50R16 | 16" | 33.00" | −0.2% | Compare |
| 33x12.50R17 | 17" | 33.00" | −0.2% | Compare |
| 33x12.50R20 | 20" | 33.00" | −0.2% | Compare |
| 33x12.50R22 | 22" | 33.00" | −0.2% | Compare |
| 315/65R17 | 17" | 33.12" | +0.2% | Compare |
One size up or down
Compare 255/75R18 with another size
Questions
- How tall is a 255/75R18 tire?
- A 255/75R18 tire is 33.1 inches tall (840 mm), calculated from the size. It is 10.0 inches wide with 7.5 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 255/75R18 mean?
- 255/75R18 means a tire 255 mm wide, with sidewalls 75% as tall as the tire is wide (191 mm), radial construction (R), for a 18 inch wheel.
- How many revolutions per mile does a 255/75R18 tire make?
- About 610 revolutions per mile, based on a circumference of 103.9 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 255/75R18 tire?
- Roughly 7.0" to 8.5". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 295/65R18 instead of 255/75R18?
- 295/65R18 is +0.04 inches (+0.1%) in overall diameter, so at an indicated 60 mph you would be doing 60.1 mph. Differences under 3% are usually fine, but check clearance, load index and your vehicle's placard.