285/45R20 tire size in inches
A 285/45R20 tire measures
30.1" tall × 11.2" wide
5.05" sidewall on a 20" wheel. 670 revolutions per mile.
285/45R20 means a tire 285 mm wide, with sidewalls 45% as tall as the tire is wide (128 mm), radial construction (R), for a 20 inch wheel.
285/45R20 specs
| Overall diameter (height) | 30.10 inches (764 mm) |
|---|---|
| Section width | 11.22 inches (285 mm) |
| Sidewall height | 5.05 inches (128 mm) |
| Wheel (rim) diameter | 20 inches |
| Circumference | 94.6 inches (2,402 mm) |
| Revolutions per mile | 670 |
| Revolutions per kilometer | 416 |
| Approximate rim width | 9.5" to 11.0" |
| In inches (flotation style) | 30.1x11.2R20 |
| Aspect ratio | 45% |
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 285/45R20 on a 20" wheel
These 20" sizes are within 3% of 285/45R20's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 215/60R20 | 30.16" | 8.46" | +0.2% | 60.1 mph | Compare |
| 255/50R20 | 30.04" | 10.04" | −0.2% | 59.9 mph | Compare |
| 235/55R20 | 30.18" | 9.25" | +0.3% | 60.2 mph | Compare |
| 325/40R20 | 30.24" | 12.80" | +0.5% | 60.3 mph | Compare |
| 315/40R20 | 29.92" | 12.40" | −0.6% | 59.6 mph | Compare |
| 355/35R20 | 29.78" | 13.98" | −1.0% | 59.4 mph | Compare |
| 265/50R20 | 30.43" | 10.43" | +1.1% | 60.7 mph | Compare |
| 225/55R20 | 29.74" | 8.86" | −1.2% | 59.3 mph | Compare |
| 275/45R20 | 29.74" | 10.83" | −1.2% | 59.3 mph | Compare |
| 295/45R20 | 30.45" | 11.61" | +1.2% | 60.7 mph | Compare |
| 245/50R20 | 29.65" | 9.65" | −1.5% | 59.1 mph | Compare |
| 335/40R20 | 30.55" | 13.19" | +1.5% | 60.9 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 235/60R19 | 19" | 30.10" | 0.0% | Compare |
| 205/75R18 | 18" | 30.11" | 0.0% | Compare |
| 275/65R16 | 16" | 30.07" | −0.1% | Compare |
| 295/35R22 | 22" | 30.13" | +0.1% | Compare |
| 255/80R14 | 14" | 30.06" | −0.1% | Compare |
| 225/85R15 | 15" | 30.06" | −0.1% | Compare |
| 255/75R15 | 15" | 30.06" | −0.1% | Compare |
| 255/70R16 | 16" | 30.06" | −0.1% | Compare |
| 255/65R17 | 17" | 30.05" | −0.2% | Compare |
| 255/60R18 | 18" | 30.05" | −0.2% | Compare |
| 345/30R22 | 22" | 30.15" | +0.2% | Compare |
| 255/55R19 | 19" | 30.04" | −0.2% | Compare |
One size up or down
- 275/45R20narrower: 29.7" × 10.8"
- 295/45R20wider: 30.5" × 11.6"
- 285/40R20lower profile: 29.0" × 11.2"
- 285/50R20taller sidewall: 31.2" × 11.2"
Compare 285/45R20 with another size
Questions
- How tall is a 285/45R20 tire?
- A 285/45R20 tire is 30.1 inches tall (764 mm), calculated from the size. It is 11.2 inches wide with 5.0 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 285/45R20 mean?
- 285/45R20 means a tire 285 mm wide, with sidewalls 45% as tall as the tire is wide (128 mm), radial construction (R), for a 20 inch wheel.
- How many revolutions per mile does a 285/45R20 tire make?
- About 670 revolutions per mile, based on a circumference of 94.6 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 285/45R20 tire?
- Roughly 9.5" to 11.0". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 215/60R20 instead of 285/45R20?
- 215/60R20 is +0.06 inches (+0.2%) 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.