235/75R15 tire size

A 235/75R15 tire is 28.88 inches (733.5 mm) tall, 9.25 in (235 mm) wide and fits a 15-inch wheel. In inch notation it is roughly a 28.9x9.3R15 — a "29-inch" tire.

235/75R15 dimensions
Overall diameter	28.88 in	733.5 mm
Section width	9.25 in	235 mm
Sidewall height	6.94 in	176.3 mm
Circumference	90.72 in	2,304 mm
Revolutions	698.4 per mile	434.0 per km
Rim diameter	15 in	381.0 mm

Compare 235/75R15 with another size

Current size

New size

Speed in mphkm/h

Overall diameter difference

+0.61%

60 mph on the speedometer = 60.4 mph actual

Within the ±3 % diameter range most tire fitters accept.

Ground clearance: +2.3 mm (+0.09 in)
Revolutions: 698 → 694 per mile

235/75R15 255/70R15

Side-by-side dimensions

	Current	New	Difference	%
Diameter	28.88 in	29.06 in	+0.18 in	+0.61%
Diameter	733.5 mm	738.0 mm	+4.5 mm	+0.61%
Width	9.25 in	10.04 in	+0.79 in	+8.51%
Width	235.0 mm	255.0 mm	+20.0 mm	+8.51%
Sidewall	6.94 in	7.03 in	+0.09 in	+1.28%
Sidewall	176.3 mm	178.5 mm	+2.3 mm	+1.28%
Circumference	90.72 in	91.28 in	+0.56 in	+0.61%
Revs per mile	698.4	694.1	−4.3	−0.61%

Speedometer error

Speedometer shows	Actual speed	Difference
20 mph	20.1 mph	+0.1 mph
30 mph	30.2 mph	+0.2 mph
40 mph	40.2 mph	+0.2 mph
50 mph	50.3 mph	+0.3 mph
60 mph	60.4 mph	+0.4 mph
70 mph	70.4 mph	+0.4 mph
80 mph	80.5 mph	+0.5 mph

Alternative sizes on the same 15-inch wheel

Sizes in use within ±3 % of the overall diameter of 235/75R15:

Plus and minus sizes for 235/75R15

Size	Wheel	Diameter	Difference
205/80R16	Plus 1 (16 in)	28.91 in	+0.12%
235/70R16	Plus 1 (16 in)	28.95 in	+0.26%
255/65R16	Plus 1 (16 in)	29.05 in	+0.60%
215/75R16	Plus 1 (16 in)	28.70 in	−0.63%
275/55R17	Plus 2 (17 in)	28.91 in	+0.11%
235/65R17	Plus 2 (17 in)	29.03 in	+0.52%
255/60R17	Plus 2 (17 in)	29.05 in	+0.59%
225/65R17	Plus 2 (17 in)	28.52 in	−1.25%
255/55R18	Plus 3 (18 in)	29.04 in	+0.57%
235/60R18	Plus 3 (18 in)	29.10 in	+0.78%
225/60R18	Plus 3 (18 in)	28.63 in	−0.86%
285/50R18	Plus 3 (18 in)	29.22 in	+1.19%

Vehicles approved with 235/75R15 tires

Models whose Swiss type approval lists 235/75R15 as a standard or optional size (110 approvals in total). Always check your own vehicle's placard or papers.

Source: Swiss Federal Roads Office (FEDRO/ASTRA), open government data. Original data (downloaded 2026-09-29). Data processed by us; errors in processing are ours, not the publisher's.

Nearby 15-inch sizes

Reading the 235/75R15 size

235 — section width in millimetres (9.25 in).
75 — aspect ratio: the sidewall is 75 % of the width, 176.3 mm.
R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
15 — fits a 15-inch diameter wheel.

The load index and speed rating (for example 91V) follow the size on the sidewall. They must meet at least the values on your vehicle's tire placard.