225/25R21 tire size in inches
A 225/25R21 tire measures
25.4" tall × 8.9" wide
2.21" sidewall on a 21" wheel. 793 revolutions per mile.
225/25R21 means a tire 225 mm wide, with sidewalls 25% as tall as the tire is wide (56 mm), radial construction (R), for a 21 inch wheel.
225/25R21 specs
| Overall diameter (height) | 25.43 inches (646 mm) |
|---|---|
| Section width | 8.86 inches (225 mm) |
| Sidewall height | 2.21 inches (56 mm) |
| Wheel (rim) diameter | 21 inches |
| Circumference | 79.9 inches (2,029 mm) |
| Revolutions per mile | 793 |
| Revolutions per kilometer | 493 |
| Approximate rim width | 7.5" to 9.0" |
| In inches (flotation style) | 25.4x8.9R21 |
| 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 225/25R21 on a 21" wheel
These 21" sizes are within 3% of 225/25R21's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 235/25R21 | 25.63" | 9.25" | +0.8% | 60.5 mph | Compare |
| 245/25R21 | 25.82" | 9.65" | +1.5% | 60.9 mph | Compare |
| 255/25R21 | 26.02" | 10.04" | +2.3% | 61.4 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 265/50R15 | 15" | 25.43" | 0.0% | Compare |
| 195/55R17 | 17" | 25.44" | +0.1% | Compare |
| 275/25R20 | 20" | 25.41" | −0.1% | Compare |
| 305/35R17 | 17" | 25.41" | −0.1% | Compare |
| 205/40R19 | 19" | 25.46" | +0.1% | Compare |
| 225/70R13 | 13" | 25.40" | −0.1% | Compare |
| 235/40R18 | 18" | 25.40" | −0.1% | Compare |
| 325/25R19 | 19" | 25.40" | −0.1% | Compare |
| 165/80R15 | 15" | 25.39" | −0.1% | Compare |
| 215/50R17 | 17" | 25.46" | +0.1% | Compare |
| 185/65R16 | 16" | 25.47" | +0.2% | Compare |
| 265/45R16 | 16" | 25.39" | −0.2% | Compare |
One size up or down
Compare 225/25R21 with another size
Questions
- How tall is a 225/25R21 tire?
- A 225/25R21 tire is 25.4 inches tall (646 mm), calculated from the size. It is 8.9 inches wide with 2.2 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 225/25R21 mean?
- 225/25R21 means a tire 225 mm wide, with sidewalls 25% as tall as the tire is wide (56 mm), radial construction (R), for a 21 inch wheel.
- How many revolutions per mile does a 225/25R21 tire make?
- About 793 revolutions per mile, based on a circumference of 79.9 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 225/25R21 tire?
- Roughly 7.5" to 9.0". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 235/25R21 instead of 225/25R21?
- 235/25R21 is +0.20 inches (+0.8%) in overall diameter, so at an indicated 60 mph you would be doing 60.5 mph. Differences under 3% are usually fine, but check clearance, load index and your vehicle's placard.