205/50R18 tire size in inches
A 205/50R18 tire measures
26.1" tall × 8.1" wide
4.04" sidewall on a 18" wheel. 774 revolutions per mile.
205/50R18 means a tire 205 mm wide, with sidewalls 50% as tall as the tire is wide (102 mm), radial construction (R), for a 18 inch wheel.
205/50R18 specs
| Overall diameter (height) | 26.07 inches (662 mm) |
|---|---|
| Section width | 8.07 inches (205 mm) |
| Sidewall height | 4.04 inches (102 mm) |
| Wheel (rim) diameter | 18 inches |
| Circumference | 81.9 inches (2,080 mm) |
| Revolutions per mile | 774 |
| Revolutions per kilometer | 481 |
| Approximate rim width | 6.0" to 7.5" |
| In inches (flotation style) | 26.1x8.1R18 |
| Aspect ratio | 50% |
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 205/50R18 on a 18" wheel
These 18" sizes are within 3% of 205/50R18's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 255/40R18 | 26.03" | 10.04" | −0.2% | 59.9 mph | Compare |
| 295/35R18 | 26.13" | 11.61" | +0.2% | 60.1 mph | Compare |
| 225/45R18 | 25.97" | 8.86" | −0.4% | 59.8 mph | Compare |
| 285/35R18 | 25.85" | 11.22" | −0.8% | 59.5 mph | Compare |
| 235/45R18 | 26.33" | 9.25" | +1.0% | 60.6 mph | Compare |
| 265/40R18 | 26.35" | 10.43" | +1.1% | 60.6 mph | Compare |
| 305/35R18 | 26.41" | 12.01" | +1.3% | 60.8 mph | Compare |
| 245/40R18 | 25.72" | 9.65" | −1.4% | 59.2 mph | Compare |
| 195/55R18 | 26.44" | 7.68" | +1.4% | 60.9 mph | Compare |
| 195/50R18 | 25.68" | 7.68" | −1.5% | 59.1 mph | Compare |
| 215/50R18 | 26.46" | 8.46" | +1.5% | 60.9 mph | Compare |
| 215/45R18 | 25.62" | 8.46" | −1.7% | 59.0 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 225/40R19 | 19" | 26.09" | +0.1% | Compare |
| 195/85R13 | 13" | 26.05" | −0.1% | Compare |
| 255/60R14 | 14" | 26.05" | −0.1% | Compare |
| 165/85R15 | 15" | 26.04" | −0.1% | Compare |
| 255/55R15 | 15" | 26.04" | −0.1% | Compare |
| 285/45R16 | 16" | 26.10" | +0.1% | Compare |
| 235/60R15 | 15" | 26.10" | +0.1% | Compare |
| 255/50R16 | 16" | 26.04" | −0.1% | Compare |
| 255/45R17 | 17" | 26.04" | −0.1% | Compare |
| 205/75R14 | 14" | 26.11" | +0.1% | Compare |
| 235/65R14 | 14" | 26.03" | −0.2% | Compare |
| 255/35R19 | 19" | 26.03" | −0.2% | Compare |
One size up or down
- 195/50R18narrower: 25.7" × 7.7"
- 215/50R18wider: 26.5" × 8.5"
- 205/45R18lower profile: 25.3" × 8.1"
- 205/55R18taller sidewall: 26.9" × 8.1"
Compare 205/50R18 with another size
Questions
- How tall is a 205/50R18 tire?
- A 205/50R18 tire is 26.1 inches tall (662 mm), calculated from the size. It is 8.1 inches wide with 4.0 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 205/50R18 mean?
- 205/50R18 means a tire 205 mm wide, with sidewalls 50% as tall as the tire is wide (102 mm), radial construction (R), for a 18 inch wheel.
- How many revolutions per mile does a 205/50R18 tire make?
- About 774 revolutions per mile, based on a circumference of 81.9 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 205/50R18 tire?
- Roughly 6.0" to 7.5". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 255/40R18 instead of 205/50R18?
- 255/40R18 is −0.04 inches (−0.2%) 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.