Flotation tire size

31x10.50R15 in metric

A 31x10.50R15 is a flotation size: 31.0 inches tall and 10.5 in wide, for a 15-inch wheel (787 × 267 mm). The closest metric sizes on the same 15-inch wheel are 265/75R15 (30.6 in). Makers publish 30.5–31.1 in for real 31x10.50R15 tires (4 makers).

Diameter31.0 in787 mm

Width10.5 in267 mm

Sidewall8.0 in203 mm

Revs per mile651nominal, published 667–687

Wheel width7–9 inapproved by every listing

Compare 31x10.50R15 with other sizes

Set up for: comparing 31x10.50R15 with a size you're considering · Different situation?

Your current size

Current tire size

e.g. 265/70R17, 2657017 or 33x12.50R20

Where do I find my size?

It's on the tire sidewall, e.g. P265/70R17 115T, and on the tire placard sticker on the driver's door jamb (also in the owner's manual). The placard shows the size the vehicle came with; the sidewall shows what is fitted now. If they differ, use the placard as your starting point. Digits are enough here: 2657017 or 33125020.

Size you're considering

Size you're considering (2)

Real 31x10.50R15 tires: published diameters

Figures from the makers' own data books. They differ from the 31.0 in calculated figure because each tread design and construction measures slightly differently.

Maker (data book)	Published diameter	Revs per mile	Approved wheel width	Listings
Falken	30.5–31.1 in	681–687	7–9 in	3
Goodyear	30.8 in	681	7–9 in	1
Hankook	30.5–30.7 in	679–686	7–9 in	2
Toyo	30.5–31.1 in	667–681	7–9 in	3

Sources: maker data books (PDF), checked 2026-11-05. Brand names identify the data source only.

Equivalent sizes on other wheels

Sizes that appear in the maker data books with a diameter within 3% of 31x10.50R15. Same diameter is only one part of fitting a different size.

Wheel	Real sizes within 3% (closest first)
15-inch	265/75R15 (30.6 in, −1.1%)
16-inch	275/70R16 (31.2 in, +0.5%), 265/70R16 (30.6 in, −1.3%), 245/75R16 (30.5 in, −1.7%)
17-inch	255/70R17 (31.1 in, +0.2%), 275/65R17 (31.1 in, +0.2%), 235/75R17 (30.9 in, −0.4%)
18-inch	275/60R18 (31.0 in, ±0.0%), 255/65R18 (31.1 in, +0.2%), 285/60R18 (31.5 in, +1.5%)
20-inch	255/55R20 (31.0 in, +0.1%), 235/60R20 (31.1 in, +0.3%), 275/50R20 (30.8 in, −0.6%)
22-inch	285/40R22 (31.0 in, −0.1%), 255/45R22 (31.0 in, +0.1%), 325/35R22 (31.0 in, −0.1%)

Popular comparisons with 31x10.50R15

265/75R16 vs 31x10.50R15−2.1% diameter 265/75R15 vs 31x10.50R15+1.1% diameter 265/70R15 vs 31x10.50R15+4.7% diameter 265/70R17 vs 31x10.50R15−1.9% diameter 235/75R15 vs 31x10.50R15+7.3% diameter 245/75R16 vs 31x10.50R15+1.7% diameter 33x12.50R15 vs 31x10.50R15−6.1% diameter 215/75R15 vs 31x10.50R15+11.9% diameter

FAQ

How tall is a 31x10.50R15 tire?

31.0 inches (787 mm) calculated from the size code. Makers publish 30.5–31.1 in for real tires in this size; the difference comes from tread design and construction.

Is 31x10.50R15 a 31-inch tire?

It is about 31.0 in tall nominally, so it is close to 31 inches. Real tires in a size vary slightly by model; check the maker's spec sheet for the exact tire.

What sizes are equivalent to 31x10.50R15?

Real sizes within 3% of its diameter include 275/70R16 (+0.5%), 255/70R17 (+0.2%), 275/60R18 (±0.0%) and 255/55R20 (+0.1%). Equal diameter alone doesn't make a size suitable: wheel width, offset, clearance and load rating all matter.

How many revolutions per mile does a 31x10.50R15 make?

About 651 calculated from its unloaded diameter. Makers publish 667–687 revs per mile, measured under load (a loaded tire rolls on a slightly smaller radius), which is why published figures are higher.

Open 31x10.50R15 in the converter · Tire size chart · 31-inch tires

Important: These are calculated (nominal) dimensions, not a fitment recommendation. Real tires of the same size differ by brand and model (makers allow about ±3% of section height), and width changes with the rim it is mounted on. The math can't see wheel width and offset, clearance at full steering lock and suspension travel, load index, speed rating, or what your vehicle maker approves. Before changing size, check your door-jamb placard and owner's manual and ask a tire professional. A replacement tire must meet or exceed the load index and speed rating on the placard.