235/65R18 in inches

A 235/65R18 tire is 30.0″ tall and 9.3″ wide, and fits a 18″ wheel. In inches it is written 30.0×9.3R18.

Diameter30.03″

Width9.25″

Sidewall6.01″

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

Manufacturer data

How tall 235/65R18 tires really are

Heights published by BFGoodrich, General, Michelin and Toyo for all 25 tires in this size. Their published revolutions per mile work out to 29.1–29.2″ under load (below).

Real 235/65R18 tires measure 30.00–30.10″, against 30.03″ from the size code. They run both taller and shorter than the size code.

Height under load29.1–29.2″

Published revs per mile (692) mean the tire rolls like a 29.1–29.2″ tire on the vehicle. Use this for speedometer calibration.

Weight spread28.7–35.3 lb

The lightest (General AltiMAX RT45, SL) is 6.6 lb lighter per corner than the heaviest (Toyo Proxes ST III, XL).

25 tires in 235/65R18

Sort by the spec you care about.

	Load					Revs/mi	Source
General AltiMAX RT45Touring	SL · 106T	30.00	28.7	11.0	2,094	692	Spec page
General AltiMAX RT45Touring	SL · 106H	30.00	28.7	11.0	2,094	692	Spec page
General AltiMAX365 AWTouring	SL · 106H	30.00	28.9	11.0	2,094	692	Spec page
Michelin CrossClimate2All-season	SL · 106V	30.00	29.1	10.0	2,094	692	Spec page
Michelin Premier LTXAll-season	SL · 106V	30.04	29.3	8.5	2,094	692	Spec page
Michelin Premier LTXAll-season	SL · 106V	30.10	29.7	8.5	2,094	692	Spec page
General Grabber H/THighway	SL · 106V	30.00	29.8	11.0	2,094	692	Spec page
Michelin Pilot Sport 4 SUVPerformance	XL · 110H	30.00	29.9	9.5	2,337	692	Spec page
Michelin Defender2All-season	SL · 106H	30.00	30.3	10.5	2,094	692	Spec page
Michelin Latitude Tour HPAll-season	XL · 110V	30.00	30.3	9.5	2,124	692	Spec page
Michelin Latitude TourAll-season	SL · 106T	30.00	30.5	10.0	1,900	692	Spec page
General Grabber H/THighway	SL · 106T	30.00	30.8	12.0	2,094	692	Spec page
Michelin Primacy Tour A/STouring	SL · 106H	30.00	30.8	9.5	2,094	692	Spec page
Toyo Extensa A/S IIAll-season	XL · 110V	30.04	31.4	10.7	2,337	692	Spec page
Toyo Celsius IITouring	SL · 106H	30.04	31.6	11.6	2,094	692	Spec page
Michelin X-Ice SnowWinter	XL · 110T	30.04	32.0	10.5	2,337	692	Spec page
Toyo Celsius CUVAll-weather	SL · 104H	30.04	32.4	11.3	1,984	692	Spec page
BFGoodrich Advantage ControlAll-season	SL · 106H	30.04	33.1	10.5	2,094	692	Spec page
General AltiMAX Arctic XWinter	XL · 110T	30.00	33.8	12.0	2,337	692	Spec page
Toyo Open Country A/T IIIAll-terrain	XL · 110T	30.04	33.8	13.0	2,337	692	Spec page
Toyo Open Country H/T IIHighway	XL · 110V	30.04	34.0	11.0	2,337	692	Spec page
Toyo Proxes G-Tour	XL · 110V	30.00	34.4	12.0	2,337	692	Spec page
Toyo Observe G3-IceWinter	XL · 110T	30.04	35.1	13.1	2,337	692	Spec page
Toyo OPEN COUNTRY Q/TAll-season	SL · 106V	30.04	35.1	11.7	2,094	692	Spec page
Toyo Proxes ST IIIPerformance	XL · 110V	30.04	35.3	10.1	2,337	692	Spec page

Is 235/65R18 a 30-inch tire?

≈30″

Yes. The size code works out to 30.03″, and the 25 tires here publish 30.00–30.10″, so people call it a 30.

All 30-inch tire sizes, on every wheel size.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 235/65R18	Difference
235/60R18	29.10	-0.93″	-3.1%
245/60R18	29.57	-0.45″	-1.5%
275/50R19	29.83	-0.20″	-0.7%
235/70R17	29.95	-0.07″	-0.2%
275/60R17	29.99	-0.04″	-0.1%
255/55R19	30.04	+0.02″	+0.1%
255/60R18	30.05	+0.02″	+0.1%
255/65R17	30.05	+0.02″	+0.1%
235/60R19	30.10	+0.07″	+0.2%
265/60R18	30.52	+0.49″	+1.6%

How to read 235/65R18

How to read any tire size

How 235/65R18 106H is printed on the sidewall. It's the most common code among the 25 tires here (6 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

265Aspect ratio

A percentage, not a measurement: the sidewall is 65% as tall as the tire is wide, which is 152.8 mm or 6.01 inches.

3RConstruction

Radial construction.

418Wheel diameter

Mounts on a 18-inch wheel. Approved wheel widths run 6.5″ to 8.5″.

5106Load index

Each tire carries up to 2,094 lb (950 kg) at its maximum pressure.

6HSpeed rating

Rated for up to 130 mph sustained.

Specification	Inches	Metric
Overall diameter	30.03	763 mm
Section width	9.25	235 mm
Sidewall height	6.01	152.8 mm
Circumference	94.3	2,396 mm
Revolutions per mile (calculated, unloaded)	671.7	417 per km
Revolutions per mile (published by manufacturers)	692	430 per km
Approved wheel width	6.5–8.5	165–216 mm

Speedometer error after switching to 235/65R18

Your actual speed– mph

Questions about 235/65R18

What is 235/65R18 in inches?

30.03 inches tall, 9.25 inches wide, on a 18-inch wheel. Written in inches, that is roughly 30.0×9.3R18.

How much does a 235/65R18 tire weigh?

Between 28.7 lb and 35.3 lb for the 25 tires listed here. The lightest is the General AltiMAX RT45 (SL); the heaviest is the Toyo Proxes ST III (XL).

What wheel width do I need for 235/65R18?

Manufacturers approve 6.5–8.5″ wide wheels for this size.

How many revolutions per mile does a 235/65R18 make?

Published figures run 692 revolutions per mile. The calculated figure is 671.7, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 235/65R18 than 245/60R18?

0.45 inches taller on paper (30.03″ vs 29.57″), which raises the axle about 0.23″. Your speedometer will read about 1.5% slow.