Tire Ruler275/50R20 dimensions
| Overall diameter (height) | 30.83″ · 783 mm |
| Section width | 10.83″ · 275 mm |
| Sidewall height | 5.41″ · 138 mm |
| Wheel diameter | 20″ |
| Rim width (rule of thumb) | 7.5–9.5″ |
| Circumference | 96.8″ |
| Revolutions per mile | 654 |
| In inches (flotation style) | 30.8 × 10.8R20 |
How it’s calculated: the sidewall is 50% of the 275 mm width = 137.5 mm (5.41″). Add two sidewalls to the 20″ wheel: 20 + 2 × 5.41 = 30.83″.
Bigger tires than 275/50R20 on 20″ wheels
| Size | Height | Taller by | 60 mph reads |
|---|---|---|---|
| 255/55R20 | 31.0″ | +0.22″ (+0.7%) | 60.4 mph |
| 285/50R20 | 31.2″ | +0.39″ (+1.3%) | 60.8 mph |
| 245/60R20 | 31.6″ | +0.75″ (+2.4%) | 61.5 mph |
| 275/55R20 | 31.9″ | +1.08″ (+3.5%) | 62.1 mph |
| 305/50R20 | 32.0″ | +1.18″ (+3.8%) | 62.3 mph |
“60 mph reads” is your real speed when a speedometer set up for 275/50R20 shows 60. Above about 3% taller, most trucks need a leveling kit or lift, and the speedometer should be recalibrated.
Sizes equivalent to 275/50R20
Within 1.5% of the same height on a 20″ wheel. Usually interchangeable for the speedometer; check width, load index and clearance.
| Size | Height | Width | Difference |
|---|---|---|---|
| 255/55R20 | 31.0″ | 10.0″ | +0.7% |
| 265/50R20 | 30.4″ | 10.4″ | −1.3% |
| 285/50R20 | 31.2″ | 11.2″ | +1.3% |
Same height on a different wheel size
Changing wheel size (plus or minus sizing) while keeping the overall height keeps your speedometer right:
- 31x10.50R15: 31.0″ tall on a 15″ wheel (+0.6%)
- 245/75R16: 30.5″ tall on a 16″ wheel (−1.2%)
- 265/70R16: 30.6″ tall on a 16″ wheel (−0.7%)
- 215/85R16: 30.4″ tall on a 16″ wheel (−1.4%)
- 245/70R17: 30.5″ tall on a 17″ wheel (−1.0%)
- 255/70R17: 31.1″ tall on a 17″ wheel (+0.7%)
- 265/65R17: 30.6″ tall on a 17″ wheel (−0.9%)
- 275/65R17: 31.1″ tall on a 17″ wheel (+0.8%)
- 265/60R18: 30.5″ tall on an 18″ wheel (−1.0%)
- 255/65R18: 31.1″ tall on an 18″ wheel (+0.7%)
- 245/65R18: 30.5″ tall on an 18″ wheel (−0.9%)
- 275/60R18: 31.0″ tall on an 18″ wheel (+0.5%)
- 255/60R19: 31.0″ tall on a 19″ wheel (+0.7%)
- 265/45R21: 30.4″ tall on a 21″ wheel (−1.4%)
- 275/45R21: 30.7″ tall on a 21″ wheel (−0.3%)
- 285/40R22: 31.0″ tall on a 22″ wheel (+0.5%)
Popular 275/50R20 comparisons
Frequently asked questions
Is 275/50R20 a 31 inch tire?
Yes. 275/50R20 is 30.83 inches tall, so it's sold and talked about as a 31-inch tire.
What size is 275/50R20 in inches?
275/50R20 is 30.8 inches tall (overall diameter), 10.8 inches wide, with a 5.4 inch sidewall, and fits a 20 inch wheel.
What tire size is equivalent to 275/50R20?
Sizes within 1.5% of the same diameter on a 20" wheel: 255/55R20 (31.0"), 265/50R20 (30.4"), 285/50R20 (31.2"). Check load index and width before swapping.
What rim width fits 275/50R20?
As a rule of thumb, about 7.5–9.5 inches. The tire maker's spec sheet lists the approved range for each model.
How many revolutions per mile does 275/50R20 make?
About 654 revolutions per mile in theory (circumference 96.8 in). Real tires turn slightly more because they flatten under load.