315/35R17 in inches

A 315/35R17 tire is 25.7″ tall and 12.4″ wide, and fits a 17″ wheel. In inches it is written 25.7×12.4R17.

Diameter25.68″

Width12.40″

Sidewall4.34″

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

Manufacturer data

How tall 315/35R17 tires really are

Heights published by Toyo for all 3 tires in this size. Their published revolutions per mile work out to 24.8–24.9″ under load (below).

Real 315/35R17 tires measure 25.57–25.67″, against 25.68″ from the size code. They run both taller and shorter than the size code.

Toyo Extensa HP II25.67″ −0.01″
Toyo Proxes R888R25.67″ −0.01″
Toyo Proxes TQ25.57″ −0.11″

Each bar runs from the size code's 25.68″ (the orange line) to the model's published height. The track spans 1.0″. Where a model comes in several load ranges, the darker part shows its range of heights; the number after the name is how many versions it comes in.

Height under load24.8–24.9″

Published revs per mile (809–813) mean the tire rolls like a 24.8–24.9″ tire on the vehicle. Use this for speedometer calibration.

Weight spread31.0–31.4 lb

The lightest (Toyo Proxes TQ, LL) is 0.4 lb lighter per corner than the heaviest (Toyo Extensa HP II, SL).

3 tires in 315/35R17

Sort by the spec you care about.

	Load					Revs/mi	Source
Toyo Proxes TQPerformance	LL	25.57	31.0	6.3	1,433	813	Spec page
Toyo Proxes R888RPerformance	SL · 102W	25.67	31.3	6.3	1,874	809	Spec page
Toyo Extensa HP IIPerformance	SL · 102W	25.67	31.4	10.5	1,874	809	Spec page

Is 315/35R17 a 26-inch tire?

≈26″

Close. The size code works out to 25.68″, and the 3 tires here publish 25.57–25.67″, so people call it a 26.

Compare with nearby sizes

Differences in overall diameter, calculated from each size code.

Size	Diameter ″	vs 315/35R17	Difference
235/45R17	25.33	-0.35″	-1.4%
265/40R17	25.35	-0.33″	-1.3%
215/50R17	25.46	-0.22″	-0.8%
275/40R17	25.66	-0.02″	-0.1%
245/45R17	25.68	0.00″	0.0%
225/50R17	25.86	+0.18″	+0.7%
205/55R17	25.88	+0.20″	+0.8%
255/45R17	26.04	+0.35″	+1.4%
195/60R17	26.21	+0.53″	+2.1%
335/35R17	26.23	+0.55″	+2.1%

How to read 315/35R17

How to read any tire size

How 315/35R17 102W is printed on the sidewall. It's the most common code among the 3 tires here (2 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

235Aspect ratio

A percentage, not a measurement: the sidewall is 35% as tall as the tire is wide, which is 110.2 mm or 4.34 inches.

3RConstruction

Radial construction.

417Wheel diameter

Mounts on a 17-inch wheel. Approved wheel widths run 10.5″ to 12.5″.

5102Load index

Each tire carries up to 1,874 lb (850 kg) at its maximum pressure.

6WSpeed rating

Rated for up to 168 mph sustained.

Specification	Inches	Metric
Overall diameter	25.68	652 mm
Section width	12.40	315 mm
Sidewall height	4.34	110.2 mm
Circumference	80.7	2,049 mm
Revolutions per mile (calculated, unloaded)	785.3	488 per km
Revolutions per mile (published by manufacturers)	809–813	503–505 per km
Approved wheel width	10.5–12.5	267–318 mm

Speedometer error after switching to 315/35R17

Your actual speed– mph

Questions about 315/35R17

What is 315/35R17 in inches?

25.68 inches tall, 12.40 inches wide, on a 17-inch wheel. Written in inches, that is roughly 25.7×12.4R17.

How much does a 315/35R17 tire weigh?

Between 31.0 lb and 31.4 lb for the 3 tires listed here. The lightest is the Toyo Proxes TQ (LL); the heaviest is the Toyo Extensa HP II (SL).

What wheel width do I need for 315/35R17?

Manufacturers approve 10.5–12.5″ wide wheels for this size.

How many revolutions per mile does a 315/35R17 make?

Published figures run 809–813 revolutions per mile. The calculated figure is 785.3, but manufacturers measure the tire under load, where it rolls on a smaller radius.

How much taller is 315/35R17 than 275/40R17?

0.02 inches taller on paper (25.68″ vs 25.66″), which raises the axle about 0.01″. Your speedometer will read about 0.1% slow.