175/55R20 tire size
175/55R20 is a metric size: 27.6" tall, 6.9" wide, on a 20" rim — about a 27.5x7.00R20. The sidewall is 3.8" and the tire turns 731 times per mile.
175/55R20 specs
| Overall diameter (height) | 27.58" · 701 mm |
|---|---|
| Section width | 6.89" · 175 mm |
| Sidewall height | 3.79" · 96 mm (55% of width) |
| Rim diameter | 20" |
| Circumference | 86.64" · 2.201 m |
| Revolutions per mile | 731 (454 per km) |
| Inch (flotation) equivalent | 27.5x7.00R20 |
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 | |
|---|---|---|---|---|---|
| 245/45R20 common | 28.68" | +4.00% | +70 mm | 62.4 mph | calculate → |
| 275/40R20 common | 28.66" | +3.93% | +100 mm | 62.4 mph | calculate → |
| 245/40R20 common | 27.72" | +0.50% | +70 mm | 60.3 mph | calculate → |
| 245/35R20 common | 26.75" | -3.00% | +70 mm | 58.2 mph | calculate → |
| 255/35R20 common | 27.03" | -2.00% | +80 mm | 58.8 mph | calculate → |
| 275/35R20 common | 27.58" | 0.00% | +100 mm | 60.0 mph | calculate → |
| 255/40R20 common | 28.03" | +1.64% | +80 mm | 61.0 mph | calculate → |
| 285/35R20 common | 27.85" | +1.00% | +110 mm | 60.6 mph | calculate → |
| 315/35R20 common | 28.68" | +4.00% | +140 mm | 62.4 mph | calculate → |
| 285/30R20 common | 26.73" | -3.07% | +110 mm | 58.2 mph | calculate → |
| 275/30R20 common | 26.50" | -3.93% | +100 mm | 57.6 mph | calculate → |
| 265/35R20 common | 27.30" | -1.00% | +90 mm | 59.4 mph | calculate → |
| 235/35R20 | 26.48" | -4.00% | +60 mm | 57.6 mph | calculate → |
| 295/30R20 | 26.97" | -2.21% | +120 mm | 58.7 mph | calculate → |
| 305/30R20 | 27.20" | -1.36% | +130 mm | 59.2 mph | calculate → |
| 295/35R20 | 28.13" | +2.00% | +120 mm | 61.2 mph | calculate → |
| 305/35R20 | 28.41" | +3.00% | +130 mm | 61.8 mph | calculate → |
| 265/30R20 | 26.26" | -4.78% | +90 mm | 57.1 mph | calculate → |
| 235/45R20 | 28.33" | +2.71% | +60 mm | 61.6 mph | calculate → |
| 225/35R20 | 26.20" | -5.00% | +50 mm | 57.0 mph | calculate → |
| 265/40R20 | 28.35" | +2.78% | +90 mm | 61.7 mph | calculate → |
| 335/25R20 | 26.59" | -3.57% | +160 mm | 57.9 mph | calculate → |
| 315/30R20 | 27.44" | -0.50% | +140 mm | 59.7 mph | calculate → |
| 235/40R20 | 27.40" | -0.64% | +60 mm | 59.6 mph | calculate → |
| 335/30R20 | 27.91" | +1.21% | +160 mm | 60.7 mph | calculate → |
| 325/25R20 | 26.40" | -4.28% | +150 mm | 57.4 mph | calculate → |
| 325/30R20 | 27.68" | +0.36% | +150 mm | 60.2 mph | calculate → |
| 345/30R20 | 28.15" | +2.07% | +170 mm | 61.2 mph | calculate → |
| 215/45R20 | 27.62" | +0.14% | +40 mm | 60.1 mph | calculate → |
| 345/25R20 | 26.79" | -2.86% | +170 mm | 58.3 mph | calculate → |
| 195/50R20 | 27.68" | +0.36% | +20 mm | 60.2 mph | calculate → |
| 225/40R20 | 27.09" | -1.78% | +50 mm | 58.9 mph | calculate → |
| 325/35R20 | 28.96" | +5.00% | +150 mm | 63.0 mph | calculate → |
| 145/65R20 | 27.42" | -0.57% | -30 mm | 59.7 mph | calculate → |
| 155/60R20 | 27.32" | -0.93% | -20 mm | 59.4 mph | calculate → |
| 145/60R20 | 26.85" | -2.64% | -30 mm | 58.4 mph | calculate → |
| 165/60R20 | 27.80" | +0.79% | -10 mm | 60.5 mph | calculate → |
| 155/65R20 | 27.93" | +1.28% | -20 mm | 60.8 mph | calculate → |
| 225/45R20 | 27.97" | +1.43% | +50 mm | 60.9 mph | calculate → |
| 195/55R20 | 28.44" | +3.14% | +20 mm | 61.9 mph | calculate → |
| 315/25R20 | 26.20" | -5.00% | +140 mm | 57.0 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 | |
|---|---|---|---|---|---|
| 245/45R19 common | 27.68" | +0.37% | +70 mm | 60.2 mph | calculate → |
| 275/40R19 common | 27.66" | +0.30% | +100 mm | 60.2 mph | calculate → |
| 235/45R19 common | 27.33" | -0.91% | +60 mm | 59.5 mph | calculate → |
| 245/35R21 | 27.75" | +0.63% | +70 mm | 60.4 mph | calculate → |
| 265/40R19 | 27.35" | -0.84% | +90 mm | 59.5 mph | calculate → |
| 285/30R21 | 27.73" | +0.56% | +110 mm | 60.3 mph | calculate → |
| 275/30R21 | 27.50" | -0.30% | +100 mm | 59.8 mph | calculate → |
| 305/35R19 | 27.41" | -0.63% | +130 mm | 59.6 mph | calculate → |
| 155/70R19 | 27.54" | -0.13% | -20 mm | 59.9 mph | calculate → |
| 355/30R19 | 27.39" | -0.70% | +180 mm | 59.6 mph | calculate → |
| 215/50R19 | 27.46" | -0.41% | +40 mm | 59.8 mph | calculate → |
| 325/25R21 | 27.40" | -0.66% | +150 mm | 59.6 mph | calculate → |
| 345/25R21 | 27.79" | +0.77% | +170 mm | 60.5 mph | calculate → |
| 315/35R19 | 27.68" | +0.37% | +140 mm | 60.2 mph | calculate → |
Try another size against 175/55R20
Questions
What size is 175/55R20 in inches?
175/55R20 is about 27.6" tall and 6.9" wide on a 20-inch rim — roughly a 27.5x7.00R20 in inch sizing.
What does 175/55R20 mean?
175 mm section width, sidewall 55% of the width (3.79"), radial construction, 20-inch rim.
What tire sizes are equivalent to 175/55R20?
On the same 20" rim, within 3% of the diameter: 275/35R20 (0.00%), 215/45R20 (+0.14%), 195/50R20 (+0.36%), 325/30R20 (+0.36%), 245/40R20 (+0.50%), 315/30R20 (-0.50%).
How many revolutions per mile does a 175/55R20 tire make?
About 731 revolutions per mile (circumference 86.6").
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.