265/60R18 vs 265/65R18 tire size
A 265/65R18 is 1.04 inches (26 mm) taller than a 265/60R18, and the same width. Fit them in place of 265/60R18 tires and the speedometer reads low: at 60 mph on it you’re doing 62.1 mph, 3.4% faster, and the vehicle sits 0.52 inches (13 mm) higher.
Sources checked
| Dimension | 265/60R18 | 265/65R18 | Change |
|---|---|---|---|
| Overall diameter | 30.52 in (775 mm) | 31.56 in (802 mm) | +1.04 in (+27 mm) |
| Section width | 10.43 in (265 mm) | 10.43 in (265 mm) | 0.00 in (0 mm) |
| Sidewall height | 6.26 in (159 mm) | 6.78 in (172 mm) | +0.52 in (+13 mm) |
| Aspect ratio | 60% | 65% | |
| Rim diameter | 18 in | 18 in | |
| Circumference | 95.9 in (2,435 mm) | 99.2 in (2,519 mm) | +3.3 in |
| Revolutions per mile | 661 | 639 | −22 |
| Revolutions per km | 411 | 397 | −14 |
Check another speed or size
Metric, LT and flotation
At 60 mph on the speedometer you’re doing
62.1mph
+3.4% · the speedometer reads low
- Height
- +1.04 in (+26 mm)
- Width
- 0.00 in (0 mm)
- Ground clearance
- +0.52 in (+13 mm)
- Each side, same wheel
- 0.00 in (0 mm)
265/60R18 and 265/65R18 side by side
| Dimension | 265/60R18 | 265/65R18 | Change |
|---|---|---|---|
| Overall diameter | 30.52 in (775 mm) | 31.56 in (802 mm) | +1.04 in (+27 mm) |
| Section width | 10.43 in (265 mm) | 10.43 in (265 mm) | 0.00 in (0 mm) |
| Sidewall height | 6.26 in (159 mm) | 6.78 in (172 mm) | +0.52 in (+13 mm) |
| Aspect ratio | 60% | 65% | |
| Rim diameter | 18 in | 18 in | |
| Circumference | 95.9 in | 99.2 in | +3.3 in |
| Revolutions per mile | 661 | 639 | −22 |
| Revolutions per km | 411 | 397 | −14 |
The working
- 265/60R18: sidewall = 265 mm × 60% = 159.0 mm = 6.26 in.
- Diameter = rim + 2 × sidewall = 18 + 2 × 6.26 = 30.52 in (775 mm).
- Circumference = π × 30.52 = 95.9 in; revolutions per mile = 63,360 ÷ 95.9 = 661.
- 265/65R18: sidewall = 265 mm × 65% = 172.3 mm = 6.78 in.
- Diameter = rim + 2 × sidewall = 18 + 2 × 6.78 = 31.56 in (802 mm).
- Circumference = π × 31.56 = 99.2 in; revolutions per mile = 63,360 ÷ 99.2 = 639.
- Speedometer. True speed = what it shows × new diameter ÷ old = 60 × 31.56 ÷ 30.52 = 62.1 mph.
- Ground clearance. Half the change in diameter: (31.56 − 30.52) ÷ 2 = +0.52 in.
Speedometer
A 265/65R18 turns 639 times a mile against the 265/60R18’s 661. With a speedometer set for 265/60R18, true speed is what it shows × 31.56 ÷ 30.52:
| Speedometer shows | True speed | Difference |
|---|---|---|
| 25 mph | 25.9 mph | +0.9 mph |
| 35 mph | 36.2 mph | +1.2 mph |
| 45 mph | 46.5 mph | +1.5 mph |
| 55 mph | 56.9 mph | +1.9 mph |
| 65 mph | 67.2 mph | +2.2 mph |
| 75 mph | 77.6 mph | +2.6 mph |
Clearance
- Ground clearance: +0.52 in (+13 mm), half the change in diameter.
- Top of the tread: +0.52 in (+13 mm), so that much less room under the fender.
- Each side, on the same wheel: no change.
A new wheel with a different width or offset moves the tire again. The sidewall goes from 6.26 to 6.78 inches.
What tire makers publish
Inflated on the maker’s measuring rim; the percentage is against the arithmetic.
| Tire | Size as printed | Diameter | Width | Revs per mile |
|---|---|---|---|---|
| Toyo Open Country A/T III | 265/60R18 | 30.5 in (−0.1%) | 10.7 in | 681 |
| Toyo Open Country A/T III | LT265/60R18 | 30.5 in (−0.1%) | 10.7 in | 681 |
| Toyo Open Country A/T III | 265/65R18 | 31.5 in (−0.2%) | 10.7 in | 659 |
| Toyo Open Country A/T III | LT265/65R18 | 31.5 in (−0.2%) | 10.7 in | 659 |
Each size on its own
- 265/60R18 tire size: 30.5 × 10.4 in
- 265/65R18 tire size: 31.6 × 10.4 in
Other comparisons
Questions
Can I fit 265/65R18 tires instead of 265/60R18?
They fit the same 18-inch wheels. A 265/65R18 is 1.04 inches (26 mm) taller than a 265/60R18, and the same width, so check three things first: that your wheels are within the 265/65R18’s approved rim width range, which tire makers list for each size; that it clears the fenders and suspension at full lock and full travel; and that its load index meets what your door-jamb placard asks for.
How far off is the speedometer with 265/65R18 tires?
With a speedometer set for 265/60R18, the speedometer reads low: at 60 mph on it you’re doing 62.1 mph, 3.4% faster. The odometer is off the same way: over 1,000 miles driven it shows 966.9.
Does 265/65R18 change the ground clearance?
By +0.52 inches (+13 mm), half the change in diameter, at the axles and at the lowest point under them. The width doesn’t change.
Sources
- Bridgestone Americas: Determining tire size: P-metric, Euro-metric, LT-metric, C-type and flotation sizes, and what each number means (checked October 28, 2026)
- Toyo Tires: Extensa A/S II sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Proxes Sport A/S sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Open Country A/T III sizes and specifications: P-metric, LT-metric and flotation sizes, with revolutions per mile (checked October 28, 2026)
- Nitto Tire: Trail Grappler M/T sizes and specs: inflated overall diameter and width, LT-metric and flotation sizes (checked October 28, 2026)
Spotted a number that doesn’t match your manual or a source? Tell us; corrections are logged on the sources page.