Tire size
245/70R17 in inches
A 245/70R17 tire is 30.5 inches tall and 9.6 inches wide, on a 17-inch wheel. Written inch-style that is about 30.5x9.6R17 (an equivalent, not a size on sale). It rounds to a 31-inch tire.
| 245/70R17 | Inches | Metric |
|---|---|---|
| Overall diameter (height) | 30.5 in | 775 mm |
| Section width | 9.6 in | 245 mm |
| Sidewall height | 6.8 in | 172 mm |
| Wheel (rim) diameter | 17 in | 432 mm |
| Circumference | 95.8 in | 2434 mm |
| Revolutions | 661 per mile | 411 per km |
How it's worked out
The 70 means the sidewall is 70% of the 245 mm width: 171.5 mm, or 6.75 in. Height = wheel + 2 sidewalls = 17 + 2 x 6.75 = 30.5 in.
Similar sizes
Sizes within about 3.5% of the height of 245/70R17. The last column is your real speed at an indicated 60 mph if your speedometer was set for 245/70R17.
| Size | Height | vs 245/70R17 | Real speed at 60 mph shown |
|---|---|---|---|
| 265/60R18 | 30.5 in | +0.1% | 60.0 mph |
| 245/75R16 | 30.5 in | -0.1% | 59.9 mph |
| 265/65R17 | 30.6 in | +0.2% | 60.1 mph |
| 265/50R20 | 30.4 in | -0.2% | 59.9 mph |
| 265/70R16 | 30.6 in | +0.3% | 60.2 mph |
| 275/50R20 | 30.8 in | +1.1% | 60.6 mph |
| 255/75R15 | 30.1 in | -1.5% | 59.1 mph |
| 255/70R16 | 30.1 in | -1.5% | 59.1 mph |
Going bigger from 245/70R17
If 245/70R17 is your stock size, these are the commonly sold axle ratios that come closest to your stock overall gearing on bigger tires.
| Your ratio now | On 33s | On 35s | On 37s |
|---|---|---|---|
| 3.21 | 3.42 exact 3.47 | 3.73 exact 3.68 | 3.91 exact 3.89 |
| 3.42 | 3.73 exact 3.70 | 3.91 exact 3.92 | 4.10 exact 4.15 |
| 3.55 | 3.91 exact 3.84 | 4.10 exact 4.07 | 4.30 exact 4.31 |
| 3.73 | 4.10 exact 4.04 | 4.30 exact 4.28 | 4.56 exact 4.52 |
| 3.91 | 4.30 exact 4.23 | 4.56 exact 4.49 | 4.88 exact 4.74 |
| 4.10 | 4.56 exact 4.44 | 4.56 exact 4.70 | 4.88 exact 4.97 |
Exact = your ratio x new height / 30.5. Front and rear axles must match on a 4WD. Not every ratio is made for every axle. Want more pull than stock? Go one step shorter. More in the regearing guide.
Questions
How tall is a 245/70R17 tire in inches?
30.5 inches (775 mm). That is the nominal height: the 17-inch wheel plus two 6.75-inch sidewalls.
What is 245/70R17 in inches?
30.5x9.6R17: 30.5 inches tall, 9.6 inches wide, for a 17-inch wheel.
Is 245/70R17 a 31-inch tire?
It measures 30.5 inches on paper, so it rounds to 31. Real tires vary a little by brand, load and wear, so check the maker's spec sheet if a fraction of an inch matters.
How many revolutions per mile does 245/70R17 do?
About 661 per mile (411 per km), from its nominal circumference of 95.8 inches.
Nominal dimensions, calculated from the size marking. Real tires differ slightly by brand, rim width, pressure and wear. Fitment depends on your vehicle, lift and wheels: this page doesn't say whether a size fits. Updated 2026-11-14.