Tire Size Inches

235/75R15 tire size in inches and millimeters

235/75R15 measures 28.88 inches in overall diameter, 9.25 inches in section width, with a 6.94 inch sidewall.

A 235/75R15 tyre drawn in section and to scale: 28.88 in overall diameter, 6.94 in of sidewall above a 15 inch wheel, and 9.25 in across the tread. The same values are in the table below it.28.88 in6.94 in9.25 in

Every dimension

Every dimension
Size In inches In millimetres
Overall diameter 28.88 in 733.5 mm
Section width 9.25 in 235 mm
Sidewall height 6.94 in 176.2 mm
Circumference 90.72 in 2,304.4 mm
Revolutions per mile 698.4 per mile 434.0 per km

Sizes that fit the same wheel

These sizes share a 15 inch wheel diameter and sit within 3% of 235/75R15 in overall diameter, which is the range a swap stays inside without recalibrating anything.

The percentage difference in overall diameter is the speedometer error: a tire 2% taller makes an indicated 60 mph a true 61.2 mph. They are the same number, so it is shown once.

Sizes that fit the same wheel
Alternate size Overall diameter Difference (in) Difference (%) Width difference (in)
295/60R15 28.94 0.06 0.20 2.36
355/50R15 28.98 0.10 0.34 4.72
205/85R15 28.72 -0.16 -0.55 -1.18
255/70R15 29.06 0.18 0.61 0.79
275/65R15 29.07 0.20 0.68 1.57
325/55R15 29.07 0.20 0.68 3.54
315/55R15 28.64 -0.24 -0.82 3.15
225/80R15 29.17 0.30 1.02 -0.39
345/50R15 28.58 -0.30 -1.02 4.33
265/65R15 28.56 -0.32 -1.09 1.18
215/80R15 28.54 -0.33 -1.16 -0.79
245/70R15 28.50 -0.37 -1.30 0.39
285/60R15 28.46 -0.41 -1.43 1.97
215/85R15 29.39 0.51 1.77 -0.79
305/60R15 29.41 0.53 1.84 2.76
225/75R15 28.29 -0.59 -2.04 -0.39
245/75R15 29.47 0.59 2.04 0.39
335/55R15 29.51 0.63 2.18 3.94
305/55R15 28.21 -0.67 -2.32 2.76
335/50R15 28.19 -0.69 -2.39 3.94
285/65R15 29.59 0.71 2.45 1.97
265/70R15 29.61 0.73 2.52 1.18
195/85R15 28.05 -0.83 -2.86 -1.57
255/65R15 28.05 -0.83 -2.86 0.79

How this is worked out

sidewall height in millimetres = section width × aspect ratio ÷ 100

overall diameter in inches = wheel diameter + (section width × aspect ratio × 2) ÷ 2540

section width in inches = section width in millimetres ÷ 25.4

circumference in inches = π × overall diameter

revolutions per mile = 63360 ÷ circumference in inches

The divisor is 2540, not the 2550 some converters publish. Two sidewalls in inches are 2 × width × aspect ÷ (100 × 25.4), and the rounding costs about 0.07 inches at 34 inches.

For 235/75R15: the sidewall is 176.2 millimetres, two of them are 13.88 inches, and adding the 15 inch wheel gives 28.88 inches overall.

Questions

What size is 235/75R15 in inches?

28.88 inches in overall diameter, 9.25 inches in section width, with a 6.94 inch sidewall.

How tall is a 235/75R15 tire?

28.88 inches, which is 733.5 millimetres.

What do the numbers in 235/75R15 mean?

235 is the section width in millimetres, 75 is the sidewall height as a percentage of that width, and 15 is the wheel diameter in inches. Overall diameter is the wheel diameter plus two sidewalls: 28.88 inches.

Does 235/75R15 fit a 15-inch wheel?

Yes — the 15 in a metric tire size *is* the wheel diameter, so 235/75R15 is made for a 15 inch wheel. Rim width is a separate question the sidewall code does not answer.

What tire sizes are equivalent to 235/75R15?

295/60R15, 355/50R15, 205/85R15 are the closest by overall diameter, all on the same 15 inch wheel.

Fitting a size is not only a matter of diameter. Rim width, load rating, speed rating and clearance all decide whether a size works on a given vehicle, and none of them can be read off the sidewall code alone.