245/30R20 tire size
245/30R20 is a metric size: 25.8" tall, 9.6" wide, on a 20" rim — about a 26x9.50R20. The sidewall is 2.9" and the tire turns 782 times per mile.
245/30R20 specs
| Overall diameter (height) | 25.79" · 655 mm |
|---|---|
| Section width | 9.65" · 245 mm |
| Sidewall height | 2.89" · 74 mm (30% of width) |
| Rim diameter | 20" |
| Circumference | 81.01" · 2.058 m |
| Revolutions per mile | 782 (486 per km) |
| Inch (flotation) equivalent | 26x9.50R20 |
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 | |
|---|---|---|---|---|---|
| 245/35R20 common | 26.75" | +3.74% | 0 mm | 62.2 mph | compare → |
| 255/35R20 common | 27.03" | +4.81% | +10 mm | 62.9 mph | compare → |
| 285/30R20 common | 26.73" | +3.66% | +40 mm | 62.2 mph | compare → |
| 275/30R20 common | 26.50" | +2.75% | +30 mm | 61.6 mph | compare → |
| 235/35R20 | 26.48" | +2.67% | -10 mm | 61.6 mph | compare → |
| 295/30R20 | 26.97" | +4.58% | +50 mm | 62.7 mph | compare → |
| 265/30R20 | 26.26" | +1.83% | +20 mm | 61.1 mph | compare → |
| 255/30R20 | 26.02" | +0.92% | +10 mm | 60.5 mph | compare → |
| 225/35R20 | 26.20" | +1.60% | -20 mm | 61.0 mph | compare → |
| 335/25R20 | 26.59" | +3.13% | +90 mm | 61.9 mph | compare → |
| 235/30R20 | 25.55" | -0.92% | -10 mm | 59.5 mph | compare → |
| 305/25R20 | 26.00" | +0.84% | +60 mm | 60.5 mph | compare → |
| 295/25R20 | 25.81" | +0.08% | +50 mm | 60.0 mph | calculate → |
| 325/25R20 | 26.40" | +2.37% | +80 mm | 61.4 mph | calculate → |
| 285/25R20 | 25.61" | -0.69% | +40 mm | 59.6 mph | calculate → |
| 225/30R20 | 25.31" | -1.83% | -20 mm | 58.9 mph | calculate → |
| 345/25R20 | 26.79" | +3.89% | +100 mm | 62.3 mph | calculate → |
| 275/25R20 | 25.41" | -1.45% | +30 mm | 59.1 mph | calculate → |
| 145/60R20 | 26.85" | +4.12% | -100 mm | 62.5 mph | calculate → |
| 315/25R20 | 26.20" | +1.60% | +70 mm | 61.0 mph | calculate → |
| 215/30R20 | 25.08" | -2.75% | -30 mm | 58.4 mph | calculate → |
Plus / minus sizing: 19" and 21" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
Try another size against 245/30R20
Questions
What size is 245/30R20 in inches?
245/30R20 is about 25.8" tall and 9.6" wide on a 20-inch rim — roughly a 26x9.50R20 in inch sizing.
What does 245/30R20 mean?
245 mm section width, sidewall 30% of the width (2.89"), radial construction, 20-inch rim.
What tire sizes are equivalent to 245/30R20?
On the same 20" rim, within 3% of the diameter: 295/25R20 (+0.08%), 285/25R20 (-0.69%), 305/25R20 (+0.84%), 235/30R20 (-0.92%), 255/30R20 (+0.92%), 275/25R20 (-1.45%).
How many revolutions per mile does a 245/30R20 tire make?
About 782 revolutions per mile (circumference 81.0").
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.