- Overall diameter
- 30.65 in77.85 cm
- Diameter change
- -1.13%
- Width change
- -1.70 mm
- Wheel diameter
- 15.00 in38.10 cm
31x10.5R15 in inches & centimeters
Starting size: Calculated from the size code: 31.00 inches tall, 10.50 inches wide, with a 8.00-inch sidewall on a 15-inch wheel.
Convert this size or compare another
Tire dimensions · 31x10.5R15
Side view
DOverall diameter31.00 in78.74 cm
SSidewall height8.00 in20.32 cm
WDWheel diameter15.00 in38.10 cm
Front view
DOverall diameter31.00 in78.74 cm
WSection width10.50 in26.67 cm
- DOverall diameter
- 31.00 in78.74 cm
- WSection width
- 10.50 in26.67 cm
- SSidewall height
- 8.00 in20.32 cm
- WDWheel diameter
- 15.00 in38.10 cm
- CCircumference
- 97.39 in247.37 cm
Approximate size in inches≈ 31.00 × 10.50R15
Diameter × width R wheel diameter, all in inches. This conversion comes from the size code; check the tire maker’s catalog for available sizes.
Enter a second size to compare it with A.
Speedometer
Add a second size to compare these results.
Wheels
Add each wheel’s width, ET and spacer thickness to compare its inner and outer edges.
Nearby sizes
Before changing size, check the tire maker’s measurements and the vehicle’s tire and wheel specifications.
All units and formulas for 31x10.5R15
Starting size: 31x10.5R15
| Measurement | inches | centimeters | millimeters |
|---|---|---|---|
| Overall diameter | 31.00 in | 78.74 cm | 787.4 mm |
| Section width | 10.50 in | 26.67 cm | 266.7 mm |
| Sidewall height | 8.00 in | 20.32 cm | 203.2 mm |
| Circumference | 97.39 in | 247.37 cm | 2,473.7 mm |
| Wheel diameter | 15.00 in | 38.10 cm | 381.0 mm |
| Revolutions / mi | 650.6 | ||
| Revolutions / km | 404.3 | ||
How we calculate it
In 31x10.5R15, 31 is the overall-diameter code in inches, 10.5 is the width code in inches and 15 is the wheel diameter in inches.
Overall diameter = 31 × 25.4 = 787.4 mm
Section width = 10.5 × 25.4 = 266.7 mm
Sidewall height = (787.4 − 15 × 25.4) / 2 = 203.2 mm
Circumference = π × 787.4 ≈ 2,473.7 mm
Read the size-code guide Section width = 10.5 × 25.4 = 266.7 mm
Sidewall height = (787.4 − 15 × 25.4) / 2 = 203.2 mm
Circumference = π × 787.4 ≈ 2,473.7 mm
Toyo Tires Open Country M/T · 31X10.50R15LT · Official size listing
The code on this tire reads 245/40 ZR18 97Y.
Product image: Continental Tire
This is the tread surface. Section width is measured across the sidewalls.
Product image: Continental TireBefore you change tire size
Check these points in the vehicle and tire specifications:
- Vehicle placard and manual: use an approved size and the required load and speed ratings.
- Wheel and tire specifications: check the approved wheel-width range and wheel offset.
- Space on the vehicle: check at full steering lock and through the suspension’s travel.
How these sizes are calculated
Dimensions come from the nominal size code. The catalog supplies the codes; the tire maker’s specification sheet supplies measurements for a particular model.
Calculation method and data sourcesSizes close to 31x10.5R15
- Overall diameter
- 30.10 in76.45 cm
- Diameter change
- -2.91%
- Width change
- +28.30 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 29.61 in75.20 cm
- Diameter change
- -4.50%
- Width change
- -1.70 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 29.06 in73.80 cm
- Diameter change
- -6.27%
- Width change
- -11.70 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 33.00 in83.82 cm
- Diameter change
- +6.45%
- Width change
- 0 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 33.00 in83.82 cm
- Diameter change
- +6.45%
- Width change
- +50.80 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 28.88 in73.35 cm
- Diameter change
- -6.85%
- Width change
- -31.70 mm
- Wheel diameter
- 15.00 in38.10 cm
- Overall diameter
- 28.29 in71.85 cm
- Diameter change
- -8.75%
- Width change
- -41.70 mm
- Wheel diameter
- 15.00 in38.10 cm
Closest diameters appear first. Check the tire maker’s measurements for the models you shortlist.