225/40R20 tire size
225/40R20 is a metric size: 27.1" tall, 8.9" wide, on a 20" rim — about a 27x9.00R20. The sidewall is 3.5" and the tire turns 745 times per mile.
225/40R20 specs
| Overall diameter (height) | 27.09" · 688 mm |
|---|---|
| Section width | 8.86" · 225 mm |
| Sidewall height | 3.54" · 90 mm (40% of width) |
| Rim diameter | 20" |
| Circumference | 85.10" · 2.161 m |
| Revolutions per mile | 745 (463 per km) |
| Inch (flotation) equivalent | 27x9.00R20 |
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" | +2.33% | +20 mm | 61.4 mph | calculate → |
| 245/35R20 common | 26.75" | -1.24% | +20 mm | 59.3 mph | calculate → |
| 255/35R20 common | 27.03" | -0.22% | +30 mm | 59.9 mph | calculate → |
| 275/35R20 common | 27.58" | +1.82% | +50 mm | 61.1 mph | calculate → |
| 255/40R20 common | 28.03" | +3.49% | +30 mm | 62.1 mph | calculate → |
| 285/35R20 common | 27.85" | +2.83% | +60 mm | 61.7 mph | calculate → |
| 285/30R20 common | 26.73" | -1.31% | +60 mm | 59.2 mph | calculate → |
| 275/30R20 common | 26.50" | -2.18% | +50 mm | 58.7 mph | calculate → |
| 265/35R20 common | 27.30" | +0.80% | +40 mm | 60.5 mph | calculate → |
| 235/35R20 | 26.48" | -2.25% | +10 mm | 58.6 mph | calculate → |
| 295/30R20 | 26.97" | -0.44% | +70 mm | 59.7 mph | calculate → |
| 305/30R20 | 27.20" | +0.44% | +80 mm | 60.3 mph | calculate → |
| 295/35R20 | 28.13" | +3.85% | +70 mm | 62.3 mph | calculate → |
| 305/35R20 | 28.41" | +4.87% | +80 mm | 62.9 mph | calculate → |
| 245/30R20 | 25.79" | -4.80% | +20 mm | 57.1 mph | calculate → |
| 265/30R20 | 26.26" | -3.05% | +40 mm | 58.2 mph | calculate → |
| 255/30R20 | 26.02" | -3.92% | +30 mm | 57.6 mph | calculate → |
| 235/45R20 | 28.33" | +4.58% | +10 mm | 62.7 mph | calculate → |
| 225/35R20 | 26.20" | -3.27% | 0 mm | 58.0 mph | calculate → |
| 265/40R20 | 28.35" | +4.65% | +40 mm | 62.8 mph | calculate → |
| 335/25R20 | 26.59" | -1.82% | +110 mm | 58.9 mph | calculate → |
| 315/30R20 | 27.44" | +1.31% | +90 mm | 60.8 mph | calculate → |
| 305/25R20 | 26.00" | -4.00% | +80 mm | 57.6 mph | calculate → |
| 235/40R20 | 27.40" | +1.16% | +10 mm | 60.7 mph | calculate → |
| 335/30R20 | 27.91" | +3.05% | +110 mm | 61.8 mph | calculate → |
| 295/25R20 | 25.81" | -4.72% | +70 mm | 57.2 mph | calculate → |
| 325/25R20 | 26.40" | -2.54% | +100 mm | 58.5 mph | calculate → |
| 325/30R20 | 27.68" | +2.18% | +100 mm | 61.3 mph | calculate → |
| 345/30R20 | 28.15" | +3.92% | +120 mm | 62.4 mph | calculate → |
| 215/45R20 | 27.62" | +1.96% | -10 mm | 61.2 mph | calculate → |
| 345/25R20 | 26.79" | -1.09% | +120 mm | 59.3 mph | calculate → |
| 195/50R20 | 27.68" | +2.18% | -30 mm | 61.3 mph | calculate → |
| 155/60R20 | 27.32" | +0.87% | -70 mm | 60.5 mph | calculate → |
| 145/60R20 | 26.85" | -0.87% | -80 mm | 59.5 mph | calculate → |
| 145/65R20 | 27.42" | +1.24% | -80 mm | 60.7 mph | calculate → |
| 175/55R20 | 27.58" | +1.82% | -50 mm | 61.1 mph | calculate → |
| 165/60R20 | 27.80" | +2.62% | -60 mm | 61.6 mph | calculate → |
| 155/65R20 | 27.93" | +3.12% | -70 mm | 61.9 mph | calculate → |
| 225/45R20 | 27.97" | +3.27% | 0 mm | 62.0 mph | calculate → |
| 315/25R20 | 26.20" | -3.27% | +90 mm | 58.0 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 | |
|---|---|---|---|---|---|
| 255/40R19 common | 27.03" | -0.20% | +30 mm | 59.9 mph | calculate → |
| 225/45R19 common | 26.97" | -0.42% | 0 mm | 59.7 mph | calculate → |
| 285/35R19 common | 26.85" | -0.86% | +60 mm | 59.5 mph | calculate → |
| 235/45R19 common | 27.33" | +0.89% | +10 mm | 60.5 mph | calculate → |
| 265/40R19 | 27.35" | +0.96% | +40 mm | 60.6 mph | calculate → |
| 295/35R19 | 27.13" | +0.16% | +70 mm | 60.1 mph | calculate → |
| 345/30R19 | 27.15" | +0.23% | +120 mm | 60.1 mph | calculate → |
| 255/30R21 | 27.02" | -0.23% | +30 mm | 59.9 mph | calculate → |
| 265/30R21 | 27.26" | +0.64% | +40 mm | 60.4 mph | calculate → |
| 305/25R21 | 27.00" | -0.31% | +80 mm | 59.8 mph | calculate → |
| 175/60R19 | 27.27" | +0.67% | -50 mm | 60.4 mph | calculate → |
| 335/30R19 | 26.91" | -0.64% | +110 mm | 59.6 mph | calculate → |
Try another size against 225/40R20
Questions
What size is 225/40R20 in inches?
225/40R20 is about 27.1" tall and 8.9" wide on a 20-inch rim — roughly a 27x9.00R20 in inch sizing.
What does 225/40R20 mean?
225 mm section width, sidewall 40% of the width (3.54"), radial construction, 20-inch rim.
What tire sizes are equivalent to 225/40R20?
On the same 20" rim, within 3% of the diameter: 255/35R20 (-0.22%), 305/30R20 (+0.44%), 295/30R20 (-0.44%), 265/35R20 (+0.80%), 155/60R20 (+0.87%), 145/60R20 (-0.87%).
How many revolutions per mile does a 225/40R20 tire make?
About 745 revolutions per mile (circumference 85.1").
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.