Metric tire size

185/55R16 tire size

A 185/55R16 tire is 24.0 inches (610 mm) tall and 7.3 in wide, for a 16-inch wheel, with a 4.0 in sidewall. That is the nominal size worked out from the code. Makers publish 23.9–24.2 in for real 185/55R16 tires (4 makers).

Diameter24.0 in610 mm

Width7.3 in185 mm

Sidewall4.0 in102 mm

Revs per mile840nominal, published 865–874

Wheel width5–6.5 inapproved by every listing

Compare 185/55R16 with other sizes

Set up for: comparing 185/55R16 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 185/55R16 tires: published diameters

Figures from the makers' own data books. They differ from the 24.0 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	24.1 in	873–874	5–6.5 in	2
Goodyear	24.2 in	872	5–6.5 in	1
Hankook	23.9 in	870	5–6.5 in	1
Toyo	24 in	865	5–6.5 in	1

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 185/55R16. Same diameter is only one part of fitting a different size.

Wheel	Real sizes within 3% (closest first)
15-inch	175/65R15 (24.0 in, −0.2%), 225/50R15 (23.9 in, −0.6%), 195/60R15 (24.2 in, +0.8%)
16-inch	225/45R16 (24.0 in, −0.2%), 205/50R16 (24.1 in, +0.2%), 175/60R16 (24.3 in, +1.1%)
17-inch	215/40R17 (23.8 in, −1.0%), 205/45R17 (24.3 in, +1.0%), 245/35R17 (23.8 in, −1.1%)
18-inch	215/35R18 (23.9 in, −0.4%), 225/35R18 (24.2 in, +0.8%), 205/35R18 (23.6 in, −1.5%)

Popular comparisons with 185/55R16

185/55R16 vs 195/50R16−1.4% diameter 185/55R16 vs 205/50R16+0.2% diameter

FAQ

How tall is a 185/55R16 tire?

24.0 inches (610 mm) calculated from the size code. Makers publish 23.9–24.2 in for real tires in this size; the difference comes from tread design and construction.

How do you work out the 185/55R16 diameter?

Sidewall = 185 mm × 55% = 101.8 mm. Diameter = 16 in wheel + 2 × 101.8 mm ÷ 25.4 = 24.01 in.

Is 185/55R16 a 24-inch tire?

It is about 24.0 in tall nominally, so it is close to 24 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 185/55R16?

Real sizes within 3% of its diameter include 215/40R17 (−1.0%) and 215/35R18 (−0.4%). 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 185/55R16 make?

About 840 calculated from its unloaded diameter. Makers publish 865–874 revs per mile, measured under load (a loaded tire rolls on a slightly smaller radius), which is why published figures are higher.

Open 185/55R16 in the converter · Tire size chart

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.