225/30R20 tire size
225/30R20 is a metric size: 25.3" tall, 8.9" wide, on a 20" rim — about a 25.5x9.00R20. The sidewall is 2.7" and the tire turns 797 times per mile.
225/30R20 specs
| Overall diameter (height) | 25.31" · 643 mm |
|---|---|
| Section width | 8.86" · 225 mm |
| Sidewall height | 2.66" · 68 mm (30% of width) |
| Rim diameter | 20" |
| Circumference | 79.53" · 2.020 m |
| Revolutions per mile | 797 (495 per km) |
| Inch (flotation) equivalent | 25.5x9.00R20 |
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 | |
|---|---|---|---|---|---|
| 275/30R20 common | 26.50" | +4.67% | +50 mm | 62.8 mph | calculate → |
| 235/35R20 | 26.48" | +4.59% | +10 mm | 62.8 mph | calculate → |
| 245/30R20 | 25.79" | +1.87% | +20 mm | 61.1 mph | calculate → |
| 265/30R20 | 26.26" | +3.73% | +40 mm | 62.2 mph | calculate → |
| 255/30R20 | 26.02" | +2.80% | +30 mm | 61.7 mph | calculate → |
| 225/35R20 | 26.20" | +3.50% | 0 mm | 62.1 mph | calculate → |
| 235/30R20 | 25.55" | +0.93% | +10 mm | 60.6 mph | calculate → |
| 305/25R20 | 26.00" | +2.72% | +80 mm | 61.6 mph | calculate → |
| 295/25R20 | 25.81" | +1.94% | +70 mm | 61.2 mph | calculate → |
| 325/25R20 | 26.40" | +4.28% | +100 mm | 62.6 mph | calculate → |
| 285/25R20 | 25.61" | +1.17% | +60 mm | 60.7 mph | calculate → |
| 275/25R20 | 25.41" | +0.39% | +50 mm | 60.2 mph | calculate → |
| 215/30R20 | 25.08" | -0.93% | -10 mm | 59.4 mph | calculate → |
| 315/25R20 | 26.20" | +3.50% | +90 mm | 62.1 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 | |
|---|---|---|---|---|---|
| 235/35R19 common | 25.48" | +0.64% | +10 mm | 60.4 mph | calculate → |
| 225/35R19 | 25.20" | -0.45% | 0 mm | 59.7 mph | calculate → |
| 275/30R19 | 25.50" | +0.72% | +50 mm | 60.4 mph | calculate → |
| 265/30R19 | 25.26" | -0.22% | +40 mm | 59.9 mph | calculate → |
| 315/25R19 | 25.20" | -0.45% | +90 mm | 59.7 mph | calculate → |
| 275/20R21 | 25.33" | +0.06% | +50 mm | 60.0 mph | calculate → |
Try another size against 225/30R20
Questions
What size is 225/30R20 in inches?
225/30R20 is about 25.3" tall and 8.9" wide on a 20-inch rim — roughly a 25.5x9.00R20 in inch sizing.
What does 225/30R20 mean?
225 mm section width, sidewall 30% of the width (2.66"), radial construction, 20-inch rim.
What tire sizes are equivalent to 225/30R20?
On the same 20" rim, within 3% of the diameter: 275/25R20 (+0.39%), 215/30R20 (-0.93%), 235/30R20 (+0.93%), 285/25R20 (+1.17%), 245/30R20 (+1.87%), 295/25R20 (+1.94%).
How many revolutions per mile does a 225/30R20 tire make?
About 797 revolutions per mile (circumference 79.5").
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.