Tire Ruler265/45R20 dimensions
| Overall diameter (height) | 29.39″ · 747 mm |
| Section width | 10.43″ · 265 mm |
| Sidewall height | 4.69″ · 119 mm |
| Wheel diameter | 20″ |
| Rim width (rule of thumb) | 7.5–9″ |
| Circumference | 92.3″ |
| Revolutions per mile | 686 |
| In inches (flotation style) | 29.4 × 10.4R20 |
How it’s calculated: the sidewall is 45% of the 265 mm width = 119.3 mm (4.69″). Add two sidewalls to the 20″ wheel: 20 + 2 × 4.69 = 29.39″.
Bigger tires than 265/45R20 on 20″ wheels
| Size | Height | Taller by | 60 mph reads |
|---|---|---|---|
| 245/50R20 | 29.6″ | +0.26″ (+0.9%) | 60.5 mph |
| 275/45R20 | 29.7″ | +0.35″ (+1.2%) | 60.7 mph |
| 255/50R20 | 30.0″ | +0.65″ (+2.2%) | 61.3 mph |
| 265/50R20 | 30.4″ | +1.04″ (+3.5%) | 62.1 mph |
| 275/50R20 | 30.8″ | +1.44″ (+4.9%) | 62.9 mph |
“60 mph reads” is your real speed when a speedometer set up for 265/45R20 shows 60. Above about 3% taller, most trucks need a leveling kit or lift, and the speedometer should be recalibrated.
Sizes equivalent to 265/45R20
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 |
|---|---|---|---|
| 245/50R20 | 29.6″ | 9.6″ | +0.9% |
| 275/45R20 | 29.7″ | 10.8″ | +1.2% |
| 255/45R20 | 29.0″ | 10.0″ | −1.2% |
Same height on a different wheel size
Changing wheel size (plus or minus sizing) while keeping the overall height keeps your speedometer right:
- 225/75R16: 29.3″ tall on a 16″ wheel (−0.3%)
- 245/70R16: 29.5″ tall on a 16″ wheel (+0.4%)
- 235/70R16: 29.0″ tall on a 16″ wheel (−1.5%)
- 245/65R17: 29.5″ tall on a 17″ wheel (+0.5%)
- 235/65R17: 29.0″ tall on a 17″ wheel (−1.2%)
- 245/60R18: 29.6″ tall on an 18″ wheel (+0.6%)
- 235/60R18: 29.1″ tall on an 18″ wheel (−1.0%)
- 255/55R18: 29.0″ tall on an 18″ wheel (−1.2%)
- 235/55R19: 29.2″ tall on a 19″ wheel (−0.7%)
- 255/50R19: 29.0″ tall on a 19″ wheel (−1.2%)
- 245/55R19: 29.6″ tall on a 19″ wheel (+0.8%)
Popular 265/45R20 comparisons
Frequently asked questions
Is 265/45R20 a 29 inch tire?
Not quite. 265/45R20 is 29.39 inches tall, between a 29 and a 30 inch tire.
What size is 265/45R20 in inches?
265/45R20 is 29.4 inches tall (overall diameter), 10.4 inches wide, with a 4.7 inch sidewall, and fits a 20 inch wheel.
What tire size is equivalent to 265/45R20?
Sizes within 1.5% of the same diameter on a 20" wheel: 245/50R20 (29.6"), 275/45R20 (29.7"), 255/45R20 (29.0"). Check load index and width before swapping.
What rim width fits 265/45R20?
As a rule of thumb, about 7.5–9 inches. The tire maker's spec sheet lists the approved range for each model.
How many revolutions per mile does 265/45R20 make?
About 686 revolutions per mile in theory (circumference 92.3 in). Real tires turn slightly more because they flatten under load.