275/55R21 tire size in inches
A 275/55R21 tire measures
32.9" tall × 10.8" wide
5.95" sidewall on a 21" wheel. 613 revolutions per mile.
275/55R21 means a tire 275 mm wide, with sidewalls 55% as tall as the tire is wide (151 mm), radial construction (R), for a 21 inch wheel.
275/55R21 specs
| Overall diameter (height) | 32.91 inches (836 mm) |
|---|---|
| Section width | 10.83 inches (275 mm) |
| Sidewall height | 5.95 inches (151 mm) |
| Wheel (rim) diameter | 21 inches |
| Circumference | 103.4 inches (2,626 mm) |
| Revolutions per mile | 613 |
| Revolutions per kilometer | 381 |
| Approximate rim width | 8.0" to 9.5" |
| In inches (flotation style) | 32.9x10.8R21 |
| Aspect ratio | 55% |
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 275/55R21 on a 21" wheel
These 21" sizes are within 3% of 275/55R21's overall diameter, the range most tire shops treat as interchangeable.
| Size | Diameter | Width | Difference | Real speed at 60 | |
|---|---|---|---|---|---|
| 335/45R21 | 32.87" | 13.19" | −0.1% | 59.9 mph | Compare |
| 305/50R21 | 33.01" | 12.01" | +0.3% | 60.2 mph | Compare |
| 295/50R21 | 32.61" | 11.61" | −0.9% | 59.5 mph | Compare |
| 345/45R21 | 33.22" | 13.58" | +1.0% | 60.6 mph | Compare |
| 325/45R21 | 32.52" | 12.80" | −1.2% | 59.3 mph | Compare |
| 265/55R21 | 32.48" | 10.43" | −1.3% | 59.2 mph | Compare |
| 285/55R21 | 33.34" | 11.22" | +1.3% | 60.8 mph | Compare |
| 315/50R21 | 33.40" | 12.40" | +1.5% | 60.9 mph | Compare |
| 355/45R21 | 33.58" | 13.98" | +2.0% | 61.2 mph | Compare |
| 285/50R21 | 32.22" | 11.22" | −2.1% | 58.7 mph | Compare |
| 355/40R21 | 32.18" | 13.98" | −2.2% | 58.7 mph | Compare |
| 315/45R21 | 32.16" | 12.40" | −2.3% | 58.6 mph | Compare |
Same height on other wheel sizes (plus and minus sizing)
| Size | Wheel | Diameter | Difference | |
|---|---|---|---|---|
| 295/60R19 | 19" | 32.94" | +0.1% | Compare |
| 315/60R18 | 18" | 32.88" | −0.1% | Compare |
| 285/80R15 | 15" | 32.95" | +0.1% | Compare |
| 345/40R22 | 22" | 32.87" | −0.1% | Compare |
| 325/35R24 | 24" | 32.96" | +0.1% | Compare |
| 285/40R24 | 24" | 32.98" | +0.2% | Compare |
| 355/50R19 | 19" | 32.98" | +0.2% | Compare |
| 285/75R16 | 16" | 32.83" | −0.2% | Compare |
| 275/60R20 | 20" | 32.99" | +0.3% | Compare |
| 275/50R22 | 22" | 32.83" | −0.3% | Compare |
| 33x12.50R15 | 15" | 33.00" | +0.3% | Compare |
| 33x12.50R16 | 16" | 33.00" | +0.3% | Compare |
One size up or down
Compare 275/55R21 with another size
Questions
- How tall is a 275/55R21 tire?
- A 275/55R21 tire is 32.9 inches tall (836 mm), calculated from the size. It is 10.8 inches wide with 6.0 inches sidewalls. Real tires vary by a few tenths of an inch between brands and tread patterns.
- What does 275/55R21 mean?
- 275/55R21 means a tire 275 mm wide, with sidewalls 55% as tall as the tire is wide (151 mm), radial construction (R), for a 21 inch wheel.
- How many revolutions per mile does a 275/55R21 tire make?
- About 613 revolutions per mile, based on a circumference of 103.4 inches. Under load the tire flattens slightly, so the maker's published figure is usually a little higher.
- What rim width fits a 275/55R21 tire?
- Roughly 8.0" to 9.5". Check the tire maker's approved rim range for the exact model before buying wheels.
- Can I use 335/45R21 instead of 275/55R21?
- 335/45R21 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.