345/25R21 tire size in inches
A 345/25R21 tire measures
27.8" tall × 13.6" wide
3.40" sidewall on a 21" wheel. 726 revolutions per mile.
345/25R21 means a tire 345 mm wide, with sidewalls 25% as tall as the tire is wide (86 mm), radial construction (R), for a 21 inch wheel.
345/25R21 specs
| Overall diameter (height) | 27.79 inches (706 mm) |
|---|---|
| Section width | 13.58 inches (345 mm) |
| Sidewall height | 3.40 inches (86 mm) |
| Wheel (rim) diameter | 21 inches |
| Circumference | 87.3 inches (2,218 mm) |
| Revolutions per mile | 726 |
| Revolutions per kilometer | 451 |
| Approximate rim width | 11.5" to 13.0" |
| In inches (flotation style) | 27.8x13.6R21 |
| Aspect ratio | 25% |
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 345/25R21 on a 21" wheel
These 21" sizes are within 3% of 345/25R21's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 245/35R21 | 27.75" | 9.65" | −0.1% | 59.9 mph | Compare |
| 285/30R21 | 27.73" | 11.22" | −0.2% | 59.9 mph | Compare |
| 295/30R21 | 27.97" | 11.61" | +0.6% | 60.4 mph | Compare |
| 355/25R21 | 27.99" | 13.98" | +0.7% | 60.4 mph | Compare |
| 335/25R21 | 27.59" | 13.19" | −0.7% | 59.6 mph | Compare |
| 255/35R21 | 28.03" | 10.04" | +0.8% | 60.5 mph | Compare |
| 225/40R21 | 28.09" | 8.86" | +1.1% | 60.6 mph | Compare |
| 275/30R21 | 27.50" | 10.83" | −1.1% | 59.4 mph | Compare |
| 235/35R21 | 27.48" | 9.25" | −1.1% | 59.3 mph | Compare |
| 325/25R21 | 27.40" | 12.80" | −1.4% | 59.2 mph | Compare |
| 305/30R21 | 28.20" | 12.01" | +1.5% | 60.9 mph | Compare |
| 265/35R21 | 28.30" | 10.43" | +1.8% | 61.1 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 245/30R22 | 22" | 27.79" | 0.0% | Compare |
| 235/80R13 | 13" | 27.80" | 0.0% | Compare |
| 295/25R22 | 22" | 27.81" | +0.1% | Compare |
| 305/45R17 | 17" | 27.81" | +0.1% | Compare |
| 275/50R17 | 17" | 27.83" | +0.1% | Compare |
| 195/70R17 | 17" | 27.75" | −0.2% | Compare |
| 225/55R18 | 18" | 27.74" | −0.2% | Compare |
| 275/45R18 | 18" | 27.74" | −0.2% | Compare |
| 215/70R16 | 16" | 27.85" | +0.2% | Compare |
| 285/35R20 | 20" | 27.85" | +0.2% | Compare |
| 225/50R19 | 19" | 27.86" | +0.2% | Compare |
| 205/85R14 | 14" | 27.72" | −0.3% | Compare |
One size up or down
- 335/25R21narrower: 27.6" × 13.2"
- 355/25R21wider: 28.0" × 14.0"
- 345/30R21taller sidewall: 29.1" × 13.6"
Compare 345/25R21 with another size
Questions
- How tall is a 345/25R21 tire?
- A 345/25R21 tire is 27.8 inches tall (706 mm), calculated from the size. It is 13.6 inches wide with 3.4 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 345/25R21 mean?
- 345/25R21 means a tire 345 mm wide, with sidewalls 25% as tall as the tire is wide (86 mm), radial construction (R), for a 21 inch wheel.
- How many revolutions per mile does a 345/25R21 tire make?
- About 726 revolutions per mile, based on a circumference of 87.3 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 345/25R21 tire?
- Roughly 11.5" to 13.0". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 245/35R21 instead of 345/25R21?
- 245/35R21 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.