265/70R18 tire size

A 265/70R18 tire is 32.6 inches (828 mm) tall and 10.4 inches (265 mm) wide, for a 18-inch wheel. Each sidewall is 7.3 inches (186 mm), 70% of the width, and the tire makes about 619 revolutions a mile.

Sources checked

Dimension265/70R18
Overall diameter32.61 in (828 mm)
Section width10.43 in (265 mm)
Sidewall height7.30 in (186 mm)
Aspect ratio70%
Rim diameter18 in
Circumference102.4 in (2,602 mm)
Revolutions per mile619
Revolutions per km384

Compare 265/70R18 with another size

Metric, LT and flotation

As printed on the sidewall: 265/70R17, LT285/75R16, 33x12.50R15.

Leave it empty to see one size on its own.

mph

Set for your tire size.

Speed unit

At 60 mph on the speedometer you’re doing

61.0mph

+1.7% · the speedometer reads low

Height
+0.55 in (+14 mm)
Width
+0.39 in (+10 mm)
Ground clearance
+0.28 in (+7 mm)
Each side, same wheel
+0.20 in (+5 mm)

265/70R18 and 275/70R18 side by side

Dimension265/70R18275/70R18Change
Overall diameter32.61 in (828 mm)33.16 in (842 mm)+0.55 in (+14 mm)
Section width10.43 in (265 mm)10.83 in (275 mm)+0.40 in (+10 mm)
Sidewall height7.30 in (186 mm)7.58 in (193 mm)+0.28 in (+7 mm)
Aspect ratio70%70%
Rim diameter18 in18 in
Circumference102.4 in104.2 in+1.8 in
Revolutions per mile619608−11
Revolutions per km384378−6

The working

  1. 265/70R18: sidewall = 265 mm × 70% = 185.5 mm = 7.30 in.
  2. Diameter = rim + 2 × sidewall = 18 + 2 × 7.30 = 32.61 in (828 mm).
  3. Circumference = π × 32.61 = 102.4 in; revolutions per mile = 63,360 ÷ 102.4 = 619.
  4. 275/70R18: sidewall = 275 mm × 70% = 192.5 mm = 7.58 in.
  5. Diameter = rim + 2 × sidewall = 18 + 2 × 7.58 = 33.16 in (842 mm).
  6. Circumference = π × 33.16 = 104.2 in; revolutions per mile = 63,360 ÷ 104.2 = 608.
  7. Speedometer. True speed = what it shows × new diameter ÷ old = 60 × 33.16 ÷ 32.61 = 61.0 mph.
  8. Ground clearance. Half the change in diameter: (33.16 − 32.61) ÷ 2 = +0.28 in.

Where the 265/70R18 numbers come from

The section width is 265 mm (10.43 inches), and each sidewall is 70% of it: 185.5 mm, or 7.30 inches. Two sidewalls and the 18-inch rim make 32.61 inches (828 mm).

One turn covers π × 32.61 = 102.4 inches, so the tire turns 619 times a mile and 384 times a kilometer.

What tire makers publish for 265/70R18

Inflated on the maker’s measuring rim. The percentage is the printed diameter against the 32.61 inches worked out above.

TireSize as printedDiameterWidthRevs per mile
Toyo Open Country A/T III265/70R1832.6 in (0.0%)10.7 in636
Toyo Open Country A/T IIILT265/70R1832.6 in (0.0%)10.7 in636

Other 18-inch sizes against 265/70R18

Each size’s height against 265/70R18, and what a speedometer set for 265/70R18 shows at 60 mph with that size on.

SizeDiameterWidthHeight changeAt 60 mph shown
225/40R1825.1 in8.9 in−23.1%46.2 mph
225/45R1826.0 in8.9 in−20.3%47.8 mph
225/55R1827.7 in8.9 in−14.9%51.1 mph
225/60R1828.6 in8.9 in−12.2%52.7 mph
235/45R1826.3 in9.3 in−19.3%48.4 mph
235/50R1827.3 in9.3 in−16.4%50.1 mph
235/55R1828.2 in9.3 in−13.6%51.8 mph
235/60R1829.1 in9.3 in−10.7%53.6 mph
235/65R1830.0 in9.3 in−7.9%55.3 mph
245/40R1825.7 in9.6 in−21.1%47.3 mph
245/45R1826.7 in9.6 in−18.2%49.1 mph
245/60R1829.6 in9.6 in−9.3%54.4 mph
255/55R1829.0 in10.0 in−10.9%53.4 mph
255/70R18 compared32.1 in10.0 in−1.7%59.0 mph
265/60R1830.5 in10.4 in−6.4%56.2 mph
265/65R18 compared31.6 in10.4 in−3.2%58.1 mph
275/65R1832.1 in10.8 in−1.6%59.0 mph
275/70R18 compared33.2 in10.8 in+1.7%61.0 mph
285/65R1832.6 in11.2 in−0.1%60.0 mph
35x12.50R1835.0 in12.5 in+7.3%64.4 mph

265/70R18 compared

Every size: the tire size calculator. With the wheels off, the nuts go back on at your vehicle’s lug nut torque.

Questions

What is 265/70R18 in inches?

About 32.6x10.4R18: 32.6 inches tall and 10.4 inches wide on a 18-inch wheel, with 7.3-inch sidewalls. Exactly, 18 + 2 × 265 mm × 0.70 ÷ 25.4 = 32.61 inches.

How many revolutions per mile does a 265/70R18 make?

619 by its diameter: 63,360 inches in a mile ÷ 102.4 inches a turn. Tire makers’ published figures are measured under load, when the tire rolls on a slightly smaller radius, and run 2.8% to 3.3% higher in Toyo’s tables.

Is LT265/70R18 the same size as P265/70R18?

In dimensions, yes: the numbers mean the same in every metric size. The letters mark what the tire is built for, and an LT tire’s load is rated differently, so check the load index and pressure your vehicle needs before swapping one for the other.

Sources

  1. 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)
  2. Toyo Tires: Extensa A/S II sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
  3. Toyo Tires: Proxes Sport A/S sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
  4. 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)
  5. 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.