tireheight.com

215/40R17 in inches

A 215/40R17 tire is 23.8″ tall and 8.5″ wide, and fits a 17″ wheel. In inches it is written 23.8×8.5R17.

Diameter23.77″
Width8.46″
Sidewall3.39″
215/40R17 drawn to scale: 23.77 inch diameter, 3.39 inch sidewall, 17 inch wheel, 8.46 inch tread width17″ wheel3.39″23.77″ overall8.46″ wideSide view
Drawn to scale. Nominal dimensions calculated from the size code.
Manufacturer data

How tall 215/40R17 tires really are

Heights published by Toyo for the one tire in this size. Their published revolutions per mile work out to 23.1″ under load (below).

The one tire listed, the Toyo Observe G3-Ice, measures 23.78″: 0.01″ taller than the size code's 23.77″.

Height under load23.1″

Published revs per mile (874) mean the tire rolls like a 23.1″ tire on the vehicle. Use this for speedometer calibration.

1 tire in 215/40R17

Sort by the spec you care about.

LoadRevs/miSource
Toyo Observe G3-IceWinterXL · 87T23.7820.511.31,201874Spec page

Is 215/40R17 a 24-inch tire?

≈24″

Yes. The size code works out to 23.77″, and the 1 tire here publishes 23.78″, so people call it a 24.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

SizeDiameter ″vs 215/40R17Difference
205/40R1723.46-0.31″-1.3%
215/45R1623.62-0.15″-0.6%
195/50R1623.68-0.09″-0.4%
245/35R1723.75-0.02″-0.1%
195/45R1723.91+0.14″+0.6%
215/35R1823.93+0.15″+0.6%
205/45R1724.26+0.49″+2.1%
235/40R1724.40+0.63″+2.6%
215/45R1724.62+0.85″+3.6%
245/40R1724.72+0.94″+4.0%

How to read 215/40R17

How to read any tire size

215/40R17 87T as printed on the tire sidewall, with each part numbered215/40R17 87T123456
How 215/40R17 87T is printed on the sidewall. It's the most common code among the 1 tire here; tires in this size come in other load and speed ratings too.
1215Section width

215 mm across the widest point, or 8.46 inches. Every 215 size

240Aspect ratio

A percentage, not a measurement: the sidewall is 40% as tall as the tire is wide, which is 86.0 mm or 3.39 inches.

3RConstruction

Radial construction.

417Wheel diameter

Mounts on a 17-inch wheel. Approved wheel widths run 7.0″ to 8.5″.

587Load index

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

6TSpeed rating

Rated for up to 118 mph sustained.

XLExtra load

Printed after the size.

SpecificationInchesMetric
Overall diameter23.77604 mm
Section width8.46215 mm
Sidewall height3.3986.0 mm
Circumference74.71,897 mm
Revolutions per mile (calculated, unloaded)848.4527 per km
Revolutions per mile (published by manufacturers)874543 per km
Approved wheel width7.0–8.5178–216 mm

Speedometer error after switching to 215/40R17

Your actual speed– mph

Questions about 215/40R17

What is 215/40R17 in inches?

23.77 inches tall, 8.46 inches wide, on a 17-inch wheel. Written in inches, that is roughly 23.8×8.5R17.

What wheel width do I need for 215/40R17?

Manufacturers approve 7.0–8.5″ wide wheels for this size.

How many revolutions per mile does a 215/40R17 make?

Published figures run 874 revolutions per mile. The calculated figure is 848.4, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 215/40R17 than 245/35R17?

0.02 inches taller on paper (23.77″ vs 23.75″), which raises the axle about 0.01″. Your speedometer will read about 0.1% slow.