315/40R26 tire size
315/40R26 is a metric size: 35.9" tall, 12.4" wide, on a 26" rim — about a 36x12.50R26. The sidewall is 5.0" and the tire turns 561 times per mile.
315/40R26 specs
| Overall diameter (height) | 35.92" · 912 mm |
|---|---|
| Section width | 12.40" · 315 mm |
| Sidewall height | 4.96" · 126 mm (40% of width) |
| Rim diameter | 26" |
| Circumference | 112.85" · 2.866 m |
| Revolutions per mile | 561 (349 per km) |
| Inch (flotation) equivalent | 36x12.50R26 |
Equivalent sizes on a 26" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 385/30R26 | 35.09" | -2.30% | +70 mm | 58.6 mph | calculate → |
| 35x13.50R26 | 35.00" | -2.56% | +28 mm | 58.5 mph | calculate → |
| 35x15.50R26 | 35.00" | -2.56% | +79 mm | 58.5 mph | calculate → |
Try another size against 315/40R26
Questions
What size is 315/40R26 in inches?
315/40R26 is about 35.9" tall and 12.4" wide on a 26-inch rim — roughly a 36x12.50R26 in inch sizing.
What does 315/40R26 mean?
315 mm section width, sidewall 40% of the width (4.96"), radial construction, 26-inch rim.
What tire sizes are equivalent to 315/40R26?
On the same 26" rim, within 3% of the diameter: 385/30R26 (-2.30%), 35x13.50R26 (-2.56%), 35x15.50R26 (-2.56%).
How many revolutions per mile does a 315/40R26 tire make?
About 561 revolutions per mile (circumference 112.8").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.