285/30R20 tire size
285/30R20 is a metric size: 26.7" tall, 11.2" wide, on a 20" rim — about a 26.5x11.00R20. The sidewall is 3.4" and the tire turns 754 times per mile.
285/30R20 specs
| Overall diameter (height) | 26.73" · 679 mm |
|---|---|
| Section width | 11.22" · 285 mm |
| Sidewall height | 3.37" · 86 mm (30% of width) |
| Rim diameter | 20" |
| Circumference | 83.98" · 2.133 m |
| Revolutions per mile | 754 (469 per km) |
| Inch (flotation) equivalent | 26.5x11.00R20 |
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 | |
|---|---|---|---|---|---|
| 245/40R20 common | 27.72" | +3.68% | -40 mm | 62.2 mph | compare → |
| 245/35R20 common | 26.75" | +0.07% | -40 mm | 60.0 mph | compare → |
| 255/35R20 common | 27.03" | +1.10% | -30 mm | 60.7 mph | compare → |
| 275/35R20 common | 27.58" | +3.17% | -10 mm | 61.9 mph | compare → |
| 255/40R20 common | 28.03" | +4.86% | -30 mm | 62.9 mph | compare → |
| 285/35R20 common | 27.85" | +4.20% | 0 mm | 62.5 mph | compare → |
| 275/30R20 common | 26.50" | -0.88% | -10 mm | 59.5 mph | compare → |
| 265/35R20 common | 27.30" | +2.14% | -20 mm | 61.3 mph | compare → |
| 235/35R20 | 26.48" | -0.96% | -50 mm | 59.4 mph | compare → |
| 295/30R20 | 26.97" | +0.88% | +10 mm | 60.5 mph | compare → |
| 305/30R20 | 27.20" | +1.77% | +20 mm | 61.1 mph | compare → |
| 245/30R20 | 25.79" | -3.53% | -40 mm | 57.9 mph | compare → |
| 265/30R20 | 26.26" | -1.77% | -20 mm | 58.9 mph | compare → |
| 255/30R20 | 26.02" | -2.65% | -30 mm | 58.4 mph | compare → |
| 225/35R20 | 26.20" | -1.99% | -60 mm | 58.8 mph | compare → |
| 335/25R20 | 26.59" | -0.52% | +50 mm | 59.7 mph | compare → |
| 315/30R20 | 27.44" | +2.65% | +30 mm | 61.6 mph | compare → |
| 235/30R20 | 25.55" | -4.42% | -50 mm | 57.3 mph | compare → |
| 305/25R20 | 26.00" | -2.72% | +20 mm | 58.4 mph | compare → |
| 235/40R20 | 27.40" | +2.50% | -50 mm | 61.5 mph | calculate → |
| 295/25R20 | 25.81" | -3.46% | +10 mm | 57.9 mph | calculate → |
| 335/30R20 | 27.91" | +4.42% | +50 mm | 62.7 mph | calculate → |
| 325/25R20 | 26.40" | -1.25% | +40 mm | 59.2 mph | calculate → |
| 325/30R20 | 27.68" | +3.53% | +40 mm | 62.1 mph | calculate → |
| 285/25R20 | 25.61" | -4.20% | 0 mm | 57.5 mph | calculate → |
| 215/45R20 | 27.62" | +3.31% | -70 mm | 62.0 mph | calculate → |
| 345/25R20 | 26.79" | +0.22% | +60 mm | 60.1 mph | calculate → |
| 225/40R20 | 27.09" | +1.33% | -60 mm | 60.8 mph | calculate → |
| 195/50R20 | 27.68" | +3.53% | -90 mm | 62.1 mph | calculate → |
| 145/60R20 | 26.85" | +0.44% | -140 mm | 60.3 mph | calculate → |
| 155/60R20 | 27.32" | +2.21% | -130 mm | 61.3 mph | calculate → |
| 145/65R20 | 27.42" | +2.58% | -140 mm | 61.5 mph | calculate → |
| 175/55R20 | 27.58" | +3.17% | -110 mm | 61.9 mph | calculate → |
| 275/25R20 | 25.41" | -4.93% | -10 mm | 57.0 mph | calculate → |
| 315/25R20 | 26.20" | -1.99% | +30 mm | 58.8 mph | calculate → |
| 165/60R20 | 27.80" | +3.98% | -120 mm | 62.4 mph | calculate → |
| 155/65R20 | 27.93" | +4.49% | -130 mm | 62.7 mph | calculate → |
| 225/45R20 | 27.97" | +4.64% | -60 mm | 62.8 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 | |
|---|---|---|---|---|---|
| 245/40R19 common | 26.72" | -0.06% | -40 mm | 60.0 mph | compare → |
| 275/35R19 common | 26.58" | -0.57% | -10 mm | 59.7 mph | compare → |
| 225/45R19 common | 26.97" | +0.90% | -60 mm | 60.5 mph | compare → |
| 285/35R19 common | 26.85" | +0.46% | 0 mm | 60.3 mph | compare → |
| 325/30R19 | 26.68" | -0.21% | +40 mm | 59.9 mph | compare → |
| 295/25R21 | 26.81" | +0.28% | +10 mm | 60.2 mph | calculate → |
| 195/50R19 | 26.68" | -0.21% | -90 mm | 59.9 mph | calculate → |
| 245/30R21 | 26.79" | +0.21% | -40 mm | 60.1 mph | calculate → |
| 335/30R19 | 26.91" | +0.68% | +50 mm | 60.4 mph | calculate → |
Try another size against 285/30R20
Questions
What size is 285/30R20 in inches?
285/30R20 is about 26.7" tall and 11.2" wide on a 20-inch rim — roughly a 26.5x11.00R20 in inch sizing.
What does 285/30R20 mean?
285 mm section width, sidewall 30% of the width (3.37"), radial construction, 20-inch rim.
What tire sizes are equivalent to 285/30R20?
On the same 20" rim, within 3% of the diameter: 245/35R20 (+0.07%), 345/25R20 (+0.22%), 145/60R20 (+0.44%), 335/25R20 (-0.52%), 275/30R20 (-0.88%), 295/30R20 (+0.88%).
How many revolutions per mile does a 285/30R20 tire make?
About 754 revolutions per mile (circumference 84.0").
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.