Conversions describe theoretical geometry. An approximate converted label is not a manufacturer-approved equivalent tire size.
Metric and inch-style tire size conversion
The converter translates the geometry represented by common metric and flotation-style size labels. Metric sizes are converted to theoretical width and diameter in inches. Flotation-style dimensions are used to estimate a nearby metric description for comparison.
Important conversion limitation
An inch-to-metric result is an approximate geometric description, not a manufacturer-approved equivalent size. Real products use discrete size standards and actual dimensions vary by model and measuring rim.
Worked example
A 285/70R17 tire has a nominal width of about 11.22 inches and a theoretical overall diameter of about 32.7 inches. The calculator shows those dimensions without claiming that a nominal 33-inch flotation tire is identical.
Sources and further checks
- NHTSA tire-safety guidance
- Your vehicle owner manual and tire-information placard
- The wheel and tire manufacturers’ current technical specifications