275/70R18 tire size
A 275/70R18 tire is 33.2 inches tall and 10.8 inches wide. Here are its full dimensions, what the numbers mean, and the sizes you can swap it for.
- Overall diameter
- 33.16″ (842 mm)
- Section width
- 10.83″ (275 mm)
- Sidewall height
- 7.58″ (193 mm)
- Wheel diameter
- 18″
- Circumference
- 104.2″
- Revolutions per mile
- 608
What 275/70R18 means
- 275: the tire is 275 mm (10.8 in) wide from sidewall to sidewall.
- 70: the sidewall is 70% of the width, 192.5 mm (7.58 in) tall.
- R: radial construction, used by almost every modern tire.
- 18: it fits a 18-inch wheel.
Overall diameter = 18 + 2 × 7.58 = 33.16 inches.
Sizes equivalent to 275/70R18
These sizes are within 3% of the overall diameter, the usual limit for swapping without speedometer problems.
| Size | Diameter | Difference | Speedometer at 60 mph |
|---|---|---|---|
| 295/65R18 | 33.1″ | -0.2% | 59.9 mph actual |
| 275/65R19 | 33.1″ | -0.2% | 59.9 mph actual |
| 255/75R18 | 33.1″ | -0.3% | 59.8 mph actual |
| 255/70R19 | 33.1″ | -0.3% | 59.8 mph actual |
| 255/65R20 | 33.1″ | -0.3% | 59.8 mph actual |
| 275/60R20 | 33.0″ | -0.5% | 59.7 mph actual |
| 295/60R19 | 32.9″ | -0.7% | 59.6 mph actual |
| 285/60R20 | 33.5″ | +0.9% | 60.6 mph actual |
| 295/55R20 | 32.8″ | -1.2% | 59.3 mph actual |
| 265/65R20 | 33.6″ | +1.2% | 60.7 mph actual |
See every common size side by side in the tire size chart.
Questions
What is 275/70R18 in inches?
A 275/70R18 tire is about 33.2 inches tall (842 mm) and 10.8 inches wide, on a 18-inch wheel. In flotation sizing that's roughly 33.2x10.8R18.
How tall is a 275/70R18 tire?
The overall diameter is 33.16 inches: the 18-inch wheel plus two 7.58-inch sidewalls. Actual tires vary by a few tenths of an inch between brands and models.
How many revolutions per mile does a 275/70R18 make?
About 608 revolutions per mile, from a circumference of 104.2 inches.
