315/30R22 in inches

A 315/30R22 tire is 29.4″ tall and 12.4″ wide, and fits a 22″ wheel. In inches it is written 29.4×12.4R22.

Diameter29.44″

Width12.40″

Sidewall3.72″

Drawn to scale. Nominal dimensions calculated from the size code.

Manufacturer data

How tall 315/30R22 tires really are

Heights published by Michelin for all 5 tires in this size. Their published revolutions per mile work out to 28.6″ under load (below).

Real 315/30R22 tires measure 29.50″, against 29.44″ from the size code. Every one runs taller than the size code.

Height under load28.6″

Published revs per mile (705) mean the tire rolls like a 28.6″ tire on the vehicle. Use this for speedometer calibration.

Weight spread33.0–34.6 lb

The lightest (Michelin Pilot Sport 4 S, XL) is 1.6 lb lighter per corner than the heaviest (Michelin Pilot Sport 4 SUV, XL).

5 tires in 315/30R22

Sort by the spec you care about.

	Load					Revs/mi	Source
Michelin Pilot Sport 4 SPerformance	XL · 107(Y)	29.50	33.0	9.0	2,149	705	Spec page
Michelin Pilot Sport All-Season 4Performance	XL · 107Y	29.50	33.3	10.0	2,149	705	Spec page
Michelin Pilot Sport 4 SPerformance	XL · 107(Y)	29.50	33.7	9.5	2,149	705	Spec page
Michelin Pilot Sport 4 SPerformance	XL · 107(Y)	29.50	33.7	8.0	2,149	705	Spec page
Michelin Pilot Sport 4 SUVPerformance	XL · 107Y	29.50	34.6	8.5	2,149	705	Spec page

Is 315/30R22 a 30-inch tire?

≈30″

Close. The size code works out to 29.44″, and the 5 tires here publish 29.50″, so people call it a 30.

All 30-inch tire sizes, on every wheel size.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 315/30R22	Difference
285/30R22	28.73	-0.71″	-2.4%
295/30R22	28.97	-0.47″	-1.6%
255/35R22	29.03	-0.41″	-1.4%
305/30R22	29.20	-0.24″	-0.8%
265/35R22	29.30	-0.14″	-0.5%
305/35R21	29.41	-0.04″	-0.1%
275/35R22	29.58	+0.14″	+0.5%
285/35R22	29.85	+0.41″	+1.4%
255/40R22	30.03	+0.59″	+2.0%
295/35R22	30.13	+0.69″	+2.3%

How to read 315/30R22

How to read any tire size

How 315/30R22 107Y is printed on the sidewall. It's the most common code among the 5 tires here (3 of them); tires in this size come in other load and speed ratings too.

1315Section width

315 mm across the widest point, or 12.40 inches. Every 315 size

230Aspect ratio

A percentage, not a measurement: the sidewall is 30% as tall as the tire is wide, which is 94.5 mm or 3.72 inches.

3RConstruction

Radial construction.

422Wheel diameter

Mounts on a 22-inch wheel. Approved wheel widths run 10.5″ to 11.5″.

5107Load index

Each tire carries up to 2,149 lb (975 kg) at its maximum pressure.

6YSpeed rating

Rated for up to 186 mph sustained.

XLExtra load

Printed after the size.

Specification	Inches	Metric
Overall diameter	29.44	748 mm
Section width	12.40	315 mm
Sidewall height	3.72	94.5 mm
Circumference	92.5	2,349 mm
Revolutions per mile (calculated, unloaded)	685.0	426 per km
Revolutions per mile (published by manufacturers)	705	438 per km
Approved wheel width	10.5–11.5	267–292 mm

Speedometer error after switching to 315/30R22

Your actual speed– mph

Questions about 315/30R22

What is 315/30R22 in inches?

29.44 inches tall, 12.40 inches wide, on a 22-inch wheel. Written in inches, that is roughly 29.4×12.4R22.

How much does a 315/30R22 tire weigh?

Between 33.0 lb and 34.6 lb for the 5 tires listed here. The lightest is the Michelin Pilot Sport 4 S (XL); the heaviest is the Michelin Pilot Sport 4 SUV (XL).

What wheel width do I need for 315/30R22?

Manufacturers approve 10.5–11.5″ wide wheels for this size.

How many revolutions per mile does a 315/30R22 make?

Published figures run 705 revolutions per mile. The calculated figure is 685.0, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 315/30R22 than 265/35R22?

0.14 inches taller on paper (29.44″ vs 29.30″), which raises the axle about 0.07″. Your speedometer will read about 0.5% slow.