325/45R20 tire size in inches
A 325/45R20 tire measures
31.5" tall × 12.8" wide
5.76" sidewall on a 20" wheel. 640 revolutions per mile.
325/45R20 means a tire 325 mm wide, with sidewalls 45% as tall as the tire is wide (146 mm), radial construction (R), for a 20 inch wheel.
325/45R20 specs
| Overall diameter (height) | 31.52 inches (801 mm) |
|---|---|
| Section width | 12.80 inches (325 mm) |
| Sidewall height | 5.76 inches (146 mm) |
| Wheel (rim) diameter | 20 inches |
| Circumference | 99.0 inches (2,515 mm) |
| Revolutions per mile | 640 |
| Revolutions per kilometer | 398 |
| Approximate rim width | 10.5" to 12.0" |
| In inches (flotation style) | 31.5x12.8R20 |
| 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 325/45R20 on a 20" wheel
These 20" sizes are within 3% of 325/45R20's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 225/65R20 | 31.52" | 8.86" | 0.0% | 60.0 mph | Compare |
| 265/55R20 | 31.48" | 10.43" | −0.1% | 59.9 mph | Compare |
| 245/60R20 | 31.57" | 9.65" | +0.2% | 60.1 mph | Compare |
| 295/50R20 | 31.61" | 11.61" | +0.3% | 60.2 mph | Compare |
| 285/50R20 | 31.22" | 11.22" | −0.9% | 59.4 mph | Compare |
| 355/40R20 | 31.18" | 13.98" | −1.1% | 59.4 mph | Compare |
| 315/45R20 | 31.16" | 12.40" | −1.1% | 59.3 mph | Compare |
| 335/45R20 | 31.87" | 13.19" | +1.1% | 60.7 mph | Compare |
| 275/55R20 | 31.91" | 10.83" | +1.2% | 60.7 mph | Compare |
| 235/60R20 | 31.10" | 9.25" | −1.3% | 59.2 mph | Compare |
| 255/55R20 | 31.04" | 10.04" | −1.5% | 59.1 mph | Compare |
| 305/50R20 | 32.01" | 12.01" | +1.6% | 60.9 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 265/60R19 | 19" | 31.52" | 0.0% | Compare |
| 345/35R22 | 22" | 31.51" | 0.0% | Compare |
| 245/70R18 | 18" | 31.50" | 0.0% | Compare |
| 245/65R19 | 19" | 31.54" | +0.1% | Compare |
| 335/40R21 | 21" | 31.55" | +0.1% | Compare |
| 245/75R17 | 17" | 31.47" | −0.1% | Compare |
| 265/65R18 | 18" | 31.56" | +0.1% | Compare |
| 285/60R18 | 18" | 31.46" | −0.2% | Compare |
| 275/35R24 | 24" | 31.58" | +0.2% | Compare |
| 295/45R21 | 21" | 31.45" | −0.2% | Compare |
| 355/45R19 | 19" | 31.58" | +0.2% | Compare |
| 285/65R17 | 17" | 31.59" | +0.2% | Compare |
One size up or down
- 315/45R20narrower: 31.2" × 12.4"
- 335/45R20wider: 31.9" × 13.2"
- 325/40R20lower profile: 30.2" × 12.8"
- 325/50R20taller sidewall: 32.8" × 12.8"
Compare 325/45R20 with another size
Questions
- How tall is a 325/45R20 tire?
- A 325/45R20 tire is 31.5 inches tall (801 mm), calculated from the size. It is 12.8 inches wide with 5.8 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 325/45R20 mean?
- 325/45R20 means a tire 325 mm wide, with sidewalls 45% as tall as the tire is wide (146 mm), radial construction (R), for a 20 inch wheel.
- How many revolutions per mile does a 325/45R20 tire make?
- About 640 revolutions per mile, based on a circumference of 99.0 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 325/45R20 tire?
- Roughly 10.5" to 12.0". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 225/65R20 instead of 325/45R20?
- 225/65R20 is 0.00 inches (0.0%) 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.