215/30R20 tire size
215/30R20 is a metric size: 25.1" tall, 8.5" wide, on a 20" rim — about a 25x8.50R20. The sidewall is 2.5" and the tire turns 804 times per mile.
215/30R20 specs
| Overall diameter (height) | 25.08" · 637 mm |
|---|---|
| Section width | 8.46" · 215 mm |
| Sidewall height | 2.54" · 65 mm (30% of width) |
| Rim diameter | 20" |
| Circumference | 78.79" · 2.001 m |
| Revolutions per mile | 804 (500 per km) |
| Inch (flotation) equivalent | 25x8.50R20 |
Equivalent sizes on a 20" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 245/30R20 | 25.79" | +2.83% | +30 mm | 61.7 mph | calculate → |
| 265/30R20 | 26.26" | +4.71% | +50 mm | 62.8 mph | calculate → |
| 255/30R20 | 26.02" | +3.77% | +40 mm | 62.3 mph | calculate → |
| 225/35R20 | 26.20" | +4.47% | +10 mm | 62.7 mph | calculate → |
| 235/30R20 | 25.55" | +1.88% | +20 mm | 61.1 mph | calculate → |
| 305/25R20 | 26.00" | +3.69% | +90 mm | 62.2 mph | calculate → |
| 295/25R20 | 25.81" | +2.90% | +80 mm | 61.7 mph | calculate → |
| 285/25R20 | 25.61" | +2.12% | +70 mm | 61.3 mph | calculate → |
| 225/30R20 | 25.31" | +0.94% | +10 mm | 60.6 mph | calculate → |
| 275/25R20 | 25.41" | +1.33% | +60 mm | 60.8 mph | calculate → |
| 315/25R20 | 26.20" | +4.47% | +100 mm | 62.7 mph | calculate → |
Plus / minus sizing: 19" and 21" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 225/35R19 | 25.20" | +0.49% | +10 mm | 60.3 mph | calculate → |
| 255/30R19 | 25.02" | -0.22% | +40 mm | 59.9 mph | calculate → |
| 265/30R19 | 25.26" | +0.72% | +50 mm | 60.4 mph | calculate → |
| 315/25R19 | 25.20" | +0.49% | +100 mm | 60.3 mph | calculate → |
| 215/35R19 | 24.93" | -0.61% | 0 mm | 59.6 mph | calculate → |
Try another size against 215/30R20
Questions
What size is 215/30R20 in inches?
215/30R20 is about 25.1" tall and 8.5" wide on a 20-inch rim — roughly a 25x8.50R20 in inch sizing.
What does 215/30R20 mean?
215 mm section width, sidewall 30% of the width (2.54"), radial construction, 20-inch rim.
What tire sizes are equivalent to 215/30R20?
On the same 20" rim, within 3% of the diameter: 225/30R20 (+0.94%), 275/25R20 (+1.33%), 235/30R20 (+1.88%), 285/25R20 (+2.12%), 245/30R20 (+2.83%), 295/25R20 (+2.90%).
How many revolutions per mile does a 215/30R20 tire make?
About 804 revolutions per mile (circumference 78.8").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.