235/75R17 in inches

A 235/75R17 tire is 30.9″ tall and 9.3″ wide, and fits a 17″ wheel. In inches it is written 30.9×9.3R17.

Diameter30.88″

Width9.25″

Sidewall6.94″

Drawn to scale. Nominal dimensions calculated from the size code.

Manufacturer data

How tall 235/75R17 tires really are

Heights published by Michelin and Toyo for all 3 tires in this size. Their published revolutions per mile work out to 29.9–30.0″ under load (below).

Real 235/75R17 tires measure 30.80–30.87″, against 30.88″ from the size code. They run both taller and shorter than the size code.

Height under load29.9–30.0″

Published revs per mile (673–674) mean the tire rolls like a 29.9–30.0″ tire on the vehicle. Use this for speedometer calibration.

Weight spread34.1–35.3 lb

The lightest (Michelin Defender LTX M/S, SL) is 1.2 lb lighter per corner than the heaviest (Toyo Open Country A/T III, SL).

3 tires in 235/75R17

Sort by the spec you care about.

	Load					Revs/mi	Source
Michelin Defender LTX M/SAll-season	SL · 109T	30.80	34.1	12.0	2,271	674	Spec page
Toyo Open Country H/T IIHighway	SL · 109T	30.87	34.6	11.8	2,271	673	Spec page
Toyo Open Country A/T IIIAll-terrain	SL · 108S	30.87	35.3	13.0	2,205	673	Spec page

Is 235/75R17 a 31-inch tire?

≈31″

Yes. The size code works out to 30.88″, and the 3 tires here publish 30.80–30.87″, so people call it a 31.

All 31-inch tire sizes, on every wheel size.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 235/75R17	Difference
275/60R17	29.99	-0.89″	-2.9%
255/65R17	30.05	-0.83″	-2.7%
225/75R17	30.29	-0.59″	-1.9%
245/70R17	30.50	-0.37″	-1.2%
265/65R17	30.56	-0.31″	-1.0%
275/60R18	30.99	+0.11″	+0.4%
255/70R17	31.06	+0.18″	+0.6%
275/65R17	31.07	+0.20″	+0.6%
245/75R17	31.47	+0.59″	+1.9%
265/70R17	31.61	+0.73″	+2.4%

How to read 235/75R17

How to read any tire size

How 235/75R17 109T is printed on the sidewall. It's the most common code among the 3 tires here (2 of them); tires in this size come in other load and speed ratings too.

1235Section width

235 mm across the widest point, or 9.25 inches. Every 235 size

275Aspect ratio

A percentage, not a measurement: the sidewall is 75% as tall as the tire is wide, which is 176.3 mm or 6.94 inches.

3RConstruction

Radial construction.

417Wheel diameter

Mounts on a 17-inch wheel. Approved wheel widths run 6.0″ to 8.0″.

5109Load index

Each tire carries up to 2,271 lb (1,030 kg) at its maximum pressure.

6TSpeed rating

Rated for up to 118 mph sustained.

Specification	Inches	Metric
Overall diameter	30.88	784 mm
Section width	9.25	235 mm
Sidewall height	6.94	176.3 mm
Circumference	97.0	2,464 mm
Revolutions per mile (calculated, unloaded)	653.2	406 per km
Revolutions per mile (published by manufacturers)	673–674	418–419 per km
Approved wheel width	6.0–8.0	152–203 mm

Speedometer error after switching to 235/75R17

Your actual speed– mph

Questions about 235/75R17

What is 235/75R17 in inches?

30.88 inches tall, 9.25 inches wide, on a 17-inch wheel. Written in inches, that is roughly 30.9×9.3R17.

How much does a 235/75R17 tire weigh?

Between 34.1 lb and 35.3 lb for the 3 tires listed here. The lightest is the Michelin Defender LTX M/S (SL); the heaviest is the Toyo Open Country A/T III (SL).

What wheel width do I need for 235/75R17?

Manufacturers approve 6.0–8.0″ wide wheels for this size.

How many revolutions per mile does a 235/75R17 make?

Published figures run 673–674 revolutions per mile. The calculated figure is 653.2, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 235/75R17 than 265/65R17?

0.31 inches taller on paper (30.88″ vs 30.56″), which raises the axle about 0.16″. Your speedometer will read about 1.0% slow.