Tire size comparison
See how two tire sizes compare.
Compare diameter, sidewall height and the theoretical speed change.
Aligned to a shared ground line
Overall diameter-8.6 mm / -1.29%
Sidewall-17 mm
At 100 km/h indicated98.71 km/h Theoretical speed
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Nominal size comparison
Aligned to a shared ground line
Every dimension
| Dimension | Original size | New size | Change |
|---|---|---|---|
| Overall diameter | 668.30 mm | 659.70 mm | -8.6 mm (-1.29%) |
| Width | 215.00 mm | 225.00 mm | +10 mm |
| Sidewall | 118.25 mm | 101.25 mm | -17 mm |
| Rim diameter | 431.80 mm | 457.20 mm | +25.4 mm |
| Circumference | 2,099.53 mm | 2,072.51 mm | -27.02 mm |
| Revolutions per km | 476.30 rev/km | 482.51 rev/km | +6.21 rev/km |
| Revolutions per mile | 766.53 rev/mi | 776.52 rev/mi | +9.99 rev/mi |
Theoretical speed
Assumes calibration to the original nominal circumference. This is not a measured road speed.
Enter 1–12 speeds separated by commas. Each must be between 0 and 400.
| Indicated speed | Theoretical speed |
|---|---|
| 30 | 29.61 |
| 50 | 49.36 |
| 60 | 59.23 |
| 100 | 98.71 |
| 120 | 118.46 |
Odometer distance estimate
Enter a distance from 0 to 1,000,000,000 using a decimal point.
Uses the same nominal circumference ratio as the speed table. This trip scenario is temporary and is not saved or exported.
Distance formula and assumptionsWhat changed?
Inner distance = width ÷ 2 + ET
A positive space change means more nominal room on the vehicle side. It does not measure clearance to any vehicle part.
Outer distance = width ÷ 2 − ET
A positive outer position change places the nominal outer edge farther out.
Convert width to millimeters first. The mounting face is fixed at zero; outward is the positive coordinate direction.
Tire bulge, rim lips, brakes, suspension, body clearance, load and speed ratings are not checked.
How we calculate