315/70R17 vs 245/70R17 tire size comparison
Change either size and everything below updates.
Start from your car make, model, year
That size does not exist: the overall diameter must be larger than the rim. The results below still show the last valid pair.
Width in mm · aspect = sidewall height as a % of width · rim in inches
Flotation (LT) sizes, all in inches: overall diameter × section width, then rim
315/70R17: 34.36″ (873 mm) tall, 12.40″ (315 mm) wide, sidewall 8.68″ (220 mm) — 587 revolutions per mile.
Not a realistic swap
−11.23% diameterA diameter change this large does not fit a stock car without a lift or other modifications. Start from the sizes your car came with.
- 70 mm narrower: check the tire is approved for your rim width.
Check what fits your car Factory tire sizes for every make, model and year.
Tires in 245/70R17
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| Measurement | 315/70R17 | 245/70R17 | Diff | % |
|---|---|---|---|---|
| Overall diameter | 34.36″873 mm | 30.50″775 mm | −3.86″ | −11.2% |
| Section width | 315.0 mm | 245.0 mm | −70.0 mm | −22.2% |
| Sidewall height | 220.5 mm | 171.5 mm | −49.0 mm | −22.2% |
| Rim diameter | 17″ | 17″ | 0″ | 0.0% |
| Circumference | 107.95″2742 mm | 95.83″2434 mm | −12.12″ | −11.2% |
| Revolutions per mileturns per distance; drives the odometer | 587365 /km | 661411 /km | +74 | +12.6% |
| Ride height change | — | — | −1.93″ −49.0 mm | |
Speedometer reading
Overlay
Plus sizing: 315/70R17 on smaller or bigger wheels
Sizes fitted to cars that keep the overall diameter within 3% of 315/70R17 on a rim one inch smaller or up to two inches bigger, closest first.
How to use the tire size calculator
Put your current tire size — width, aspect ratio and rim diameter — into the first form, then your desired size into the second. You’ll get the difference between the new and the old size, plus the speedometer reading difference and your actual speed on the new set. Both metric and flotation (LT inch) sizes are supported.
The calculator helps you decide whether a set of tires and wheels will fit your car. To compare tires by brand and model instead, use our tire comparison tool; to look up factory sizes, browse by car make.
Changing wheels too? The wheel offset calculator shows how far a new wheel width and offset move the tire toward the suspension and the fender.
Reading a tire size
- 225
- Section width in millimetres
- 45
- Aspect ratio — sidewall height as a % of width
- R
- Radial construction
- 17
- Rim diameter in inches