275/55R18 tire size in inches
A 275/55R18 tire measures
29.9" tall × 10.8" wide
5.95" sidewall on a 18" wheel. 674 revolutions per mile.
275/55R18 means a tire 275 mm wide, with sidewalls 55% as tall as the tire is wide (151 mm), radial construction (R), for a 18 inch wheel.
275/55R18 specs
| Overall diameter (height) | 29.91 inches (760 mm) |
|---|---|
| Section width | 10.83 inches (275 mm) |
| Sidewall height | 5.95 inches (151 mm) |
| Wheel (rim) diameter | 18 inches |
| Circumference | 94.0 inches (2,387 mm) |
| Revolutions per mile | 674 |
| Revolutions per kilometer | 419 |
| Approximate rim width | 8.0" to 9.5" |
| In inches (flotation style) | 29.9x10.8R18 |
| Aspect ratio | 55% |
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 275/55R18 on a 18" wheel
These 18" sizes are within 3% of 275/55R18's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 335/45R18 | 29.87" | 13.19" | −0.1% | 59.9 mph | Compare |
| 215/70R18 | 29.85" | 8.46" | −0.2% | 59.9 mph | Compare |
| 305/50R18 | 30.01" | 12.01" | +0.3% | 60.2 mph | Compare |
| 235/65R18 | 30.03" | 9.25" | +0.4% | 60.2 mph | Compare |
| 255/60R18 | 30.05" | 10.04" | +0.5% | 60.3 mph | Compare |
| 205/75R18 | 30.11" | 8.07" | +0.7% | 60.4 mph | Compare |
| 295/50R18 | 29.61" | 11.61" | −1.0% | 59.4 mph | Compare |
| 245/60R18 | 29.57" | 9.65" | −1.1% | 59.3 mph | Compare |
| 195/75R18 | 29.52" | 7.68" | −1.3% | 59.2 mph | Compare |
| 225/65R18 | 29.52" | 8.86" | −1.3% | 59.2 mph | Compare |
| 325/45R18 | 29.52" | 12.80" | −1.3% | 59.2 mph | Compare |
| 265/55R18 | 29.48" | 10.43" | −1.4% | 59.1 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 335/30R22 | 22" | 29.91" | 0.0% | Compare |
| 315/40R20 | 20" | 29.92" | 0.0% | Compare |
| 295/60R16 | 16" | 29.94" | +0.1% | Compare |
| 235/75R16 | 16" | 29.88" | −0.1% | Compare |
| 345/40R19 | 19" | 29.87" | −0.1% | Compare |
| 235/70R17 | 17" | 29.95" | +0.1% | Compare |
| 325/35R21 | 21" | 29.96" | +0.2% | Compare |
| 225/50R21 | 21" | 29.86" | −0.2% | Compare |
| 285/35R22 | 22" | 29.85" | −0.2% | Compare |
| 285/40R21 | 21" | 29.98" | +0.2% | Compare |
| 275/50R19 | 19" | 29.83" | −0.3% | Compare |
| 275/60R17 | 17" | 29.99" | +0.3% | Compare |
One size up or down
- 265/55R18narrower: 29.5" × 10.4"
- 285/55R18wider: 30.3" × 11.2"
- 275/50R18lower profile: 28.8" × 10.8"
- 275/60R18taller sidewall: 31.0" × 10.8"
Compare 275/55R18 with another size
Questions
- How tall is a 275/55R18 tire?
- A 275/55R18 tire is 29.9 inches tall (760 mm), calculated from the size. It is 10.8 inches wide with 6.0 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 275/55R18 mean?
- 275/55R18 means a tire 275 mm wide, with sidewalls 55% as tall as the tire is wide (151 mm), radial construction (R), for a 18 inch wheel.
- How many revolutions per mile does a 275/55R18 tire make?
- About 674 revolutions per mile, based on a circumference of 94.0 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 275/55R18 tire?
- Roughly 8.0" to 9.5". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 335/45R18 instead of 275/55R18?
- 335/45R18 is −0.04 inches (−0.1%) in overall diameter, so at an indicated 60 mph you would be doing 59.9 mph. Differences under 3% are usually fine, but check clearance, load index and your vehicle's placard.