tireheight.com

185/55R16 in inches

A 185/55R16 tire is 24.0″ tall and 7.3″ wide, and fits a 16″ wheel. In inches it is written 24.0×7.3R16.

Diameter24.01″
Width7.28″
Sidewall4.01″
185/55R16 drawn to scale: 24.01 inch diameter, 4.01 inch sidewall, 16 inch wheel, 7.28 inch tread width16″ wheel4.01″24.01″ overall7.28″ wideSide view
Drawn to scale. Nominal dimensions calculated from the size code.
Manufacturer data

How tall 185/55R16 tires really are

Heights published by General, Michelin and Toyo for all 4 tires in this size. Their published revolutions per mile work out to 23.3″ under load (below).

Real 185/55R16 tires measure 24.00–24.02″, against 24.01″ from the size code. They run both taller and shorter than the size code.

Height under load23.3″

Published revs per mile (865–866) mean the tire rolls like a 23.3″ tire on the vehicle. Use this for speedometer calibration.

Weight spread17.5–20.3 lb

The lightest (General AltiMAX RT45, XL) is 2.8 lb lighter per corner than the heaviest (Michelin X-Ice Snow, XL).

4 tires in 185/55R16

Sort by the spec you care about.

LoadRevs/miSource
General AltiMAX RT45TouringXL · 87H24.0017.511.01,201865Spec page
Toyo Extensa HP IIPerformanceSL · 83V24.0218.28.81,074865Spec page
Toyo Observe G3-IceWinterXL · 87T24.0219.611.31,201865Spec page
Michelin X-Ice SnowWinterXL · 87H24.0220.310.51,201866Spec page

Is 185/55R16 a 24-inch tire?

≈24″

Yes. The size code works out to 24.01″, and the 4 tires here publish 24.00–24.02″, so people call it a 24.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

SizeDiameter ″vs 185/55R16Difference
205/45R1623.26-0.75″-3.1%
215/45R1623.62-0.39″-1.6%
195/50R1623.68-0.33″-1.4%
175/65R1523.96-0.06″-0.2%
225/45R1623.97-0.04″-0.2%
205/50R1624.07+0.06″+0.2%
195/55R1624.44+0.43″+1.8%
245/45R1624.68+0.67″+2.8%
185/60R1624.74+0.73″+3.0%
225/50R1624.86+0.85″+3.5%

How to read 185/55R16

How to read any tire size

185/55R16 87H as printed on the tire sidewall, with each part numbered185/55R16 87H123456
How 185/55R16 87H is printed on the sidewall. It's the most common code among the 4 tires here (2 of them); tires in this size come in other load and speed ratings too.
1185Section width

185 mm across the widest point, or 7.28 inches. Every 185 size

255Aspect ratio

A percentage, not a measurement: the sidewall is 55% as tall as the tire is wide, which is 101.8 mm or 4.01 inches.

3RConstruction

Radial construction.

416Wheel diameter

Mounts on a 16-inch wheel. Approved wheel widths run 5.0″ to 6.5″.

587Load index

Each tire carries up to 1,201 lb (545 kg) at its maximum pressure.

6HSpeed rating

Rated for up to 130 mph sustained.

XLExtra load

Printed after the size. In this size the XL tires carry up to 1,201 lb each and the standard-load tires up to 1,074 lb, as published.

SpecificationInchesMetric
Overall diameter24.01610 mm
Section width7.28185 mm
Sidewall height4.01101.8 mm
Circumference75.41,916 mm
Revolutions per mile (calculated, unloaded)839.9522 per km
Revolutions per mile (published by manufacturers)865–866537–538 per km
Approved wheel width5.0–6.5127–165 mm

Speedometer error after switching to 185/55R16

Your actual speed– mph

Questions about 185/55R16

What is 185/55R16 in inches?

24.01 inches tall, 7.28 inches wide, on a 16-inch wheel. Written in inches, that is roughly 24.0×7.3R16.

How much does a 185/55R16 tire weigh?

Between 17.5 lb and 20.3 lb for the 4 tires listed here. The lightest is the General AltiMAX RT45 (XL); the heaviest is the Michelin X-Ice Snow (XL).

What wheel width do I need for 185/55R16?

Manufacturers approve 5.0–6.5″ wide wheels for this size.

How many revolutions per mile does a 185/55R16 make?

Published figures run 865–866 revolutions per mile. The calculated figure is 839.9, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 185/55R16 than 225/45R16?

0.04 inches taller on paper (24.01″ vs 23.97″), which raises the axle about 0.02″. Your speedometer will read about 0.2% slow.