275/65R18 tire size
A 275/65R18 tire is 32.1 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
- 32.07″ (815 mm)
- Section width
- 10.83″ (275 mm)
- Sidewall height
- 7.04″ (179 mm)
- Wheel diameter
- 18″
- Circumference
- 100.8″
- Revolutions per mile
- 629
What 275/65R18 means
- 275: the tire is 275 mm (10.8 in) wide from sidewall to sidewall.
- 65: the sidewall is 65% of the width, 178.8 mm (7.04 in) tall.
- R: radial construction, used by almost every modern tire.
- 18: it fits a 18-inch wheel.
Overall diameter = 18 + 2 × 7.04 = 32.07 inches.
Sizes equivalent to 275/65R18
These sizes are within 3% of the overall diameter, the usual limit for swapping without speedometer problems.
| Size | Diameter | Difference | Speedometer at 60 mph |
|---|---|---|---|
| 255/70R18 | 32.1″ | -0.1% | 60.0 mph actual |
| 255/65R19 | 32.1″ | -0.1% | 60.0 mph actual |
| 255/60R20 | 32.0″ | -0.1% | 59.9 mph actual |
| 275/60R19 | 32.0″ | -0.3% | 59.8 mph actual |
| 295/60R18 | 31.9″ | -0.4% | 59.7 mph actual |
| 275/55R20 | 31.9″ | -0.5% | 59.7 mph actual |
| 285/55R20 | 32.3″ | +0.8% | 60.5 mph actual |
| 295/55R19 | 31.8″ | -0.9% | 59.4 mph actual |
| 285/60R19 | 32.5″ | +1.2% | 60.7 mph actual |
| 265/60R20 | 32.5″ | +1.4% | 60.8 mph actual |
Going a size taller? 285/65R18 is 32.6″ tall, 1.6% more than 275/65R18. Compare any two sizes in the tire size calculator.
See every common size side by side in the tire size chart.
Questions
What is 275/65R18 in inches?
A 275/65R18 tire is about 32.1 inches tall (815 mm) and 10.8 inches wide, on a 18-inch wheel. In flotation sizing that's roughly 32.1x10.8R18.
How tall is a 275/65R18 tire?
The overall diameter is 32.07 inches: the 18-inch wheel plus two 7.04-inch sidewalls. Actual tires vary by a few tenths of an inch between brands and models.
Can I put 285/65R18 instead of 275/65R18?
285/65R18 is 0.51 inches taller (1.6%) and 10 mm wider. That's within the usual 3% limit, but check that your wheel width is approved for it and that it clears the suspension.
How many revolutions per mile does a 275/65R18 make?
About 629 revolutions per mile, from a circumference of 100.8 inches.
