235/40R19 tire size

A 235/40R19 tire is 26.4 inches (671 mm) tall and 9.3 inches (235 mm) wide, for a 19-inch wheel. Each sidewall is 3.7 inches (94 mm), 40% of the width, and the tire makes about 764 revolutions a mile.

Sources checked

Dimension235/40R19
Overall diameter26.40 in (671 mm)
Section width9.25 in (235 mm)
Sidewall height3.70 in (94 mm)
Aspect ratio40%
Rim diameter19 in
Circumference82.9 in (2,107 mm)
Revolutions per mile764
Revolutions per km475

Compare 235/40R19 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

60.7mph

+1.2% · the speedometer reads low

Height
+0.31 in (+8 mm)
Width
+0.39 in (+10 mm)
Ground clearance
+0.16 in (+4 mm)
Each side, same wheel
+0.20 in (+5 mm)

235/40R19 and 245/40R19 side by side

Dimension235/40R19245/40R19Change
Overall diameter26.40 in (671 mm)26.72 in (679 mm)+0.32 in (+8 mm)
Section width9.25 in (235 mm)9.65 in (245 mm)+0.40 in (+10 mm)
Sidewall height3.70 in (94 mm)3.86 in (98 mm)+0.16 in (+4 mm)
Aspect ratio40%40%
Rim diameter19 in19 in
Circumference82.9 in83.9 in+1.0 in
Revolutions per mile764755−9
Revolutions per km475469−6

The working

  1. 235/40R19: sidewall = 235 mm × 40% = 94.0 mm = 3.70 in.
  2. Diameter = rim + 2 × sidewall = 19 + 2 × 3.70 = 26.40 in (671 mm).
  3. Circumference = π × 26.40 = 82.9 in; revolutions per mile = 63,360 ÷ 82.9 = 764.
  4. 245/40R19: sidewall = 245 mm × 40% = 98.0 mm = 3.86 in.
  5. Diameter = rim + 2 × sidewall = 19 + 2 × 3.86 = 26.72 in (679 mm).
  6. Circumference = π × 26.72 = 83.9 in; revolutions per mile = 63,360 ÷ 83.9 = 755.
  7. Speedometer. True speed = what it shows × new diameter ÷ old = 60 × 26.72 ÷ 26.40 = 60.7 mph.
  8. Ground clearance. Half the change in diameter: (26.72 − 26.40) ÷ 2 = +0.16 in.

Where the 235/40R19 numbers come from

The section width is 235 mm (9.25 inches), and each sidewall is 40% of it: 94.0 mm, or 3.70 inches. Two sidewalls and the 19-inch rim make 26.40 inches (671 mm).

One turn covers π × 26.40 = 82.9 inches, so the tire turns 764 times a mile and 475 times a kilometer.

What tire makers publish for 235/40R19

Inflated on the maker’s measuring rim. The percentage is the printed diameter against the 26.40 inches worked out above.

TireSize as printedDiameterWidthRevs per mile
Toyo Extensa A/S II235/40R1926.4 in (0.0%)9.5 in786
Toyo Proxes Sport A/S235/40R1926.4 in (0.0%)9.5 in786

Other 19-inch sizes against 235/40R19

Each size’s height against 235/40R19, and what a speedometer set for 235/40R19 shows at 60 mph with that size on.

SizeDiameterWidthHeight changeAt 60 mph shown
235/55R1929.2 in9.3 in+10.5%66.3 mph
245/40R19 compared26.7 in9.6 in+1.2%60.7 mph
245/45R1927.7 in9.6 in+4.8%62.9 mph
255/55R1930.0 in10.0 in+13.8%68.3 mph

235/40R19 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 235/40R19 in inches?

About 26.4x9.3R19: 26.4 inches tall and 9.3 inches wide on a 19-inch wheel, with 3.7-inch sidewalls. Exactly, 19 + 2 × 235 mm × 0.40 ÷ 25.4 = 26.40 inches.

How many revolutions per mile does a 235/40R19 make?

764 by its diameter: 63,360 inches in a mile ÷ 82.9 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 LT235/40R19 the same size as P235/40R19?

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.