315/70R17 tire size
A 315/70R17 tire is 34.4 inches (873 mm) tall and 12.4 inches (315 mm) wide, for a 17-inch wheel. Each sidewall is 8.7 inches (220 mm), 70% of the width, and the tire makes about 587 revolutions a mile.
Sources checked
| Dimension | 315/70R17 |
|---|---|
| Overall diameter | 34.36 in (873 mm) |
| Section width | 12.40 in (315 mm) |
| Sidewall height | 8.68 in (220 mm) |
| Aspect ratio | 70% |
| Rim diameter | 17 in |
| Circumference | 108.0 in (2,742 mm) |
| Revolutions per mile | 587 |
| Revolutions per km | 365 |
Compare 315/70R17 with another size
Metric, LT and flotation
At 60 mph on the speedometer you’re doing
61.1mph
+1.9% · the speedometer reads low
- Height
- +0.64 in (+16 mm)
- Width
- +0.10 in (+2 mm)
- Ground clearance
- +0.32 in (+8 mm)
- Each side, same wheel
- +0.05 in (+1 mm)
315/70R17 and 35x12.50R17LT side by side
| Dimension | 315/70R17 | 35x12.50R17LT | Change |
|---|---|---|---|
| Overall diameter | 34.36 in (873 mm) | 35.00 in (889 mm) | +0.64 in (+16 mm) |
| Section width | 12.40 in (315 mm) | 12.50 in (318 mm) | +0.10 in (+3 mm) |
| Sidewall height | 8.68 in (220 mm) | 9.00 in (229 mm) | +0.32 in (+9 mm) |
| Aspect ratio | 70% | 72% | |
| Rim diameter | 17 in | 17 in | |
| Circumference | 108.0 in | 110.0 in | +2.0 in |
| Revolutions per mile | 587 | 576 | −11 |
| Revolutions per km | 365 | 358 | −7 |
The working
- 315/70R17: sidewall = 315 mm × 70% = 220.5 mm = 8.68 in.
- Diameter = rim + 2 × sidewall = 17 + 2 × 8.68 = 34.36 in (873 mm).
- Circumference = π × 34.36 = 108.0 in; revolutions per mile = 63,360 ÷ 108.0 = 587.
- 35x12.50R17LT: 35.00 in tall and 12.50 in wide, as the size says.
- Sidewall = (diameter − rim) ÷ 2 = (35 − 17) ÷ 2 = 9.00 in.
- Circumference = π × 35.00 = 110.0 in; revolutions per mile = 63,360 ÷ 110.0 = 576.
- Speedometer. True speed = what it shows × new diameter ÷ old = 60 × 35.00 ÷ 34.36 = 61.1 mph.
- Ground clearance. Half the change in diameter: (35.00 − 34.36) ÷ 2 = +0.32 in.
Where the 315/70R17 numbers come from
The section width is 315 mm (12.40 inches), and each sidewall is 70% of it: 220.5 mm, or 8.68 inches. Two sidewalls and the 17-inch rim make 34.36 inches (873 mm).
One turn covers π × 34.36 = 108.0 inches, so the tire turns 587 times a mile and 365 times a kilometer.
What tire makers publish for 315/70R17
Inflated on the maker’s measuring rim. The percentage is the printed diameter against the 34.36 inches worked out above.
| Tire | Size as printed | Diameter | Width | Revs per mile |
|---|---|---|---|---|
| Toyo Open Country A/T III | LT315/70R17 | 34.4 in (+0.1%) | 12.7 in | 604 |
| Nitto Trail Grappler M/T | LT315/70R17 | 34.61 in (+0.7%) | 13.27 in | – |
Other 17-inch sizes against 315/70R17
Each size’s height against 315/70R17, and what a speedometer set for 315/70R17 shows at 60 mph with that size on.
| Size | Diameter | Width | Height change | At 60 mph shown |
|---|---|---|---|---|
| 215/45R17 | 24.6 in | 8.5 in | −28.4% | 43.0 mph |
| 215/50R17 | 25.5 in | 8.5 in | −25.9% | 44.5 mph |
| 215/55R17 | 26.3 in | 8.5 in | −23.4% | 45.9 mph |
| 215/60R17 | 27.2 in | 8.5 in | −21.0% | 47.4 mph |
| 225/45R17 | 25.0 in | 8.9 in | −27.3% | 43.6 mph |
| 225/50R17 | 25.9 in | 8.9 in | −24.7% | 45.2 mph |
| 225/55R17 | 26.7 in | 8.9 in | −22.2% | 46.7 mph |
| 225/60R17 | 27.6 in | 8.9 in | −19.6% | 48.2 mph |
| 225/65R17 | 28.5 in | 8.9 in | −17.0% | 49.8 mph |
| 235/55R17 | 27.2 in | 9.3 in | −20.9% | 47.5 mph |
| 235/60R17 | 28.1 in | 9.3 in | −18.2% | 49.1 mph |
| 235/65R17 | 29.0 in | 9.3 in | −15.5% | 50.7 mph |
| 245/65R17 | 29.5 in | 9.6 in | −14.0% | 51.6 mph |
| 245/70R17 | 30.5 in | 9.6 in | −11.2% | 53.3 mph |
| 245/75R17 | 31.5 in | 9.6 in | −8.4% | 54.9 mph |
| 255/70R17 | 31.1 in | 10.0 in | −9.6% | 54.2 mph |
| 265/65R17 | 30.6 in | 10.4 in | −11.1% | 53.4 mph |
| 265/70R17 | 31.6 in | 10.4 in | −8.0% | 55.2 mph |
| 275/70R17 | 32.2 in | 10.8 in | −6.4% | 56.2 mph |
| 285/70R17 | 32.7 in | 11.2 in | −4.8% | 57.1 mph |
| 285/75R17 | 33.8 in | 11.2 in | −1.5% | 59.1 mph |
| 33x12.50R17 | 33.0 in | 12.5 in | −4.0% | 57.6 mph |
| 35x12.50R17 compared | 35.0 in | 12.5 in | +1.9% | 61.1 mph |
| 37x12.50R17 | 37.0 in | 12.5 in | +7.7% | 64.6 mph |
315/70R17 compared
Every size: the tire size calculator. With the wheels off, the nuts go back on at your vehicle’s lug nut torque.
Questions
What is 315/70R17 in inches?
About 34.4x12.4R17: 34.4 inches tall and 12.4 inches wide on a 17-inch wheel, with 8.7-inch sidewalls. Exactly, 17 + 2 × 315 mm × 0.70 ÷ 25.4 = 34.36 inches.
How many revolutions per mile does a 315/70R17 make?
587 by its diameter: 63,360 inches in a mile ÷ 108.0 inches a turn. Tire makers’ published figures are measured under load, when the tire rolls on a slightly smaller radius, and run 2.8% to 3.3% higher in Toyo’s tables.
What flotation size is closest to 315/70R17?
Of the common 17-inch sizes, 35x12.50R17: 0.64 inches (16 mm) taller and 0.10 inches (2 mm) wider.
Is LT315/70R17 the same size as P315/70R17?
In dimensions, yes: the numbers mean the same in every metric size. The letters mark what the tire is built for, and an LT tire’s load is rated differently, so check the load index and pressure your vehicle needs before swapping one for the other.
Sources
- Bridgestone Americas: Determining tire size: P-metric, Euro-metric, LT-metric, C-type and flotation sizes, and what each number means (checked October 28, 2026)
- Toyo Tires: Extensa A/S II sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Proxes Sport A/S sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Open Country A/T III sizes and specifications: P-metric, LT-metric and flotation sizes, with revolutions per mile (checked October 28, 2026)
- Nitto Tire: Trail Grappler M/T sizes and specs: inflated overall diameter and width, LT-metric and flotation sizes (checked October 28, 2026)
Spotted a number that doesn’t match your manual or a source? Tell us; corrections are logged on the sources page.