Tire Height Calculator
"Tire height" is the marketing word for overall diameter. Get it in inches and millimetres for any metric size, and compare against the common sizes in the chart.
Overall diameter31.61 in
Diameter (metric)803 mm
Sidewall height7.30 in
Circumference99.29 in
Revs per mile638
height (in) = (rim × 25.4 + 2 × width × aspect ÷ 100) ÷ 25.4
Imperial equivalents: a "33-inch tire" measured by this formula is the nominal spec height. Most 33s measure 32.5–33.2 in real life; LT flotation sizes (like 33×12.50R15) are usually shorter than their label too.
Common tire heights (computed)
| Size | Diameter | Metric | Revs/mile |
|---|---|---|---|
| 205/55R16 | 24.88 in | 632 mm | 811 |
| 215/60R16 | 26.16 in | 664 mm | 771 |
| 225/55R17 | 26.74 in | 679 mm | 754 |
| 235/45R18 | 26.33 in | 669 mm | 766 |
| 245/40R19 | 26.72 in | 679 mm | 755 |
| 255/70R16 | 30.06 in | 763 mm | 671 |
| 265/70R17 | 31.61 in | 803 mm | 638 |
| 285/70R17 | 32.71 in | 831 mm | 617 |
| 285/75R16 | 32.83 in | 834 mm | 614 |
| 305/70R16 | 32.81 in | 833 mm | 615 |
| 315/75R16 | 34.60 in | 879 mm | 583 |
| 35x12.5R17 | 35.03 in | 890 mm | 576 |
Every row is computed by the same engine as the calculator above — nominal spec-sheet height, real tires vary ±0.2–0.4 in.
Assumptions & sources
Height formula(rim×25.4 + 2×width×aspect/100) ÷ 25.4Standard tire geometry
Label vs. measuredusually −0.5 to +0.2 inCommunity measurements on LT/metric sizes
Frequently asked questions
What size is a 33-inch tire in metric?
There is no single metric equivalent, but 285/70R17 and 285/75R16 both compute to about 32.7 in — close to a true 33. Use the calculator with your real candidates rather than trusting the label.
How much taller is a 265/70R17 than a 245/75R16?
265/70R17 computes to 31.6 in; 245/75R16 to 30.5 in — about 1.1 in (3.6%) taller, which is inside the grey zone. Check the comparison calculator for the speedometer effect.
Does tire height affect gas mileage?
Yes, two ways: taller tires raise gearing (fewer revs per mile, often better highway mpg, worse acceleration) and usually add weight and rolling resistance. Real-world changes of 1–3 mpg are commonly reported after upsizing.