255/30R20 tire size in inches
A 255/30R20 tire measures
26.0" tall × 10.0" wide
3.01" sidewall on a 20" wheel. 775 revolutions per mile.
255/30R20 means a tire 255 mm wide, with sidewalls 30% as tall as the tire is wide (77 mm), radial construction (R), for a 20 inch wheel.
255/30R20 specs
| Overall diameter (height) | 26.02 inches (661 mm) |
|---|---|
| Section width | 10.04 inches (255 mm) |
| Sidewall height | 3.01 inches (77 mm) |
| Wheel (rim) diameter | 20 inches |
| Circumference | 81.8 inches (2,077 mm) |
| Revolutions per mile | 775 |
| Revolutions per kilometer | 482 |
| Approximate rim width | 8.5" to 10.0" |
| In inches (flotation style) | 26.0x10.0R20 |
| Aspect ratio | 30% |
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 255/30R20 on a 20" wheel
These 20" sizes are within 3% of 255/30R20's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 305/25R20 | 26.00" | 12.01" | −0.1% | 60.0 mph | Compare |
| 215/35R20 | 25.93" | 8.46" | −0.4% | 59.8 mph | Compare |
| 225/35R20 | 26.20" | 8.86" | +0.7% | 60.4 mph | Compare |
| 315/25R20 | 26.20" | 12.40" | +0.7% | 60.4 mph | Compare |
| 295/25R20 | 25.81" | 11.61" | −0.8% | 59.5 mph | Compare |
| 265/30R20 | 26.26" | 10.43" | +0.9% | 60.5 mph | Compare |
| 245/30R20 | 25.79" | 9.65" | −0.9% | 59.5 mph | Compare |
| 325/25R20 | 26.40" | 12.80" | +1.4% | 60.9 mph | Compare |
| 285/25R20 | 25.61" | 11.22" | −1.6% | 59.0 mph | Compare |
| 235/35R20 | 26.48" | 9.25" | +1.7% | 61.0 mph | Compare |
| 275/30R20 | 26.50" | 10.83" | +1.8% | 61.1 mph | Compare |
| 235/30R20 | 25.55" | 9.25" | −1.8% | 58.9 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 175/80R15 | 15" | 26.02" | 0.0% | Compare |
| 235/65R14 | 14" | 26.03" | 0.0% | Compare |
| 255/35R19 | 19" | 26.03" | 0.0% | Compare |
| 255/25R21 | 21" | 26.02" | 0.0% | Compare |
| 255/40R18 | 18" | 26.03" | 0.0% | Compare |
| 255/45R17 | 17" | 26.04" | 0.0% | Compare |
| 255/50R16 | 16" | 26.04" | +0.1% | Compare |
| 165/85R15 | 15" | 26.04" | +0.1% | Compare |
| 255/55R15 | 15" | 26.04" | +0.1% | Compare |
| 215/65R15 | 15" | 26.00" | −0.1% | Compare |
| 255/60R14 | 14" | 26.05" | +0.1% | Compare |
| 195/85R13 | 13" | 26.05" | +0.1% | Compare |
One size up or down
- 245/30R20narrower: 25.8" × 9.6"
- 265/30R20wider: 26.3" × 10.4"
- 255/25R20lower profile: 25.0" × 10.0"
- 255/35R20taller sidewall: 27.0" × 10.0"
Compare 255/30R20 with another size
Questions
- How tall is a 255/30R20 tire?
- A 255/30R20 tire is 26.0 inches tall (661 mm), calculated from the size. It is 10.0 inches wide with 3.0 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 255/30R20 mean?
- 255/30R20 means a tire 255 mm wide, with sidewalls 30% as tall as the tire is wide (77 mm), radial construction (R), for a 20 inch wheel.
- How many revolutions per mile does a 255/30R20 tire make?
- About 775 revolutions per mile, based on a circumference of 81.8 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 255/30R20 tire?
- Roughly 8.5" to 10.0". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 305/25R20 instead of 255/30R20?
- 305/25R20 is −0.02 inches (−0.1%) in overall diameter, so at an indicated 60 mph you would be doing 60.0 mph. Differences under 3% are usually fine, but check clearance, load index and your vehicle's placard.