245/70R17 vs 275/65R17
275/65R17 is taller than 245/70R17 by 1.87% — a diameter difference of 0.57″.
What changes between 245/70R17 and 275/65R17
Switching from 245/70R17 to 275/65R17 changes overall diameter by +1.87%, a taller tire by 0.57 inches. This lands inside the ±3% fitment safe zone, so most vehicles will accept the swap without rubbing, speedometer recalibration, or ABS/TPMS complications. Section width moves by +1.18″ (245mm → 275mm), which affects contact patch and fender-well clearance. Sidewall height shifts by +0.29″: a taller sidewall softens ride quality and adds off-road bump protection, with some loss of steering crispness. Revs per mile moves by -12, which translates directly to speedometer error — at an indicated 65 mph, actual speed becomes 66.2 mph. Both sizes share the same 17″ rim, so no wheel change is required — this is a pure tire-only swap.
| Spec | 245/70R17 | 275/65R17 |
|---|---|---|
| Overall diameter | 30.5″ | 31.07″ |
| Section width | 9.65″ (245 mm) | 10.83″ (275 mm) |
| Sidewall height | 6.75″ (70%) | 7.04″ (65%) |
| Rim diameter | 17″ | 17″ |
| Circumference | 95.83″ | 97.62″ |
| Revs per mile | 661 | 649 |
Interactive comparison
275/65R18 or "33" for inch aliases245/70R17
- Diameter
- 30.5″ / 774.8mm
- Section Width
- 9.65″
- Sidewall
- 6.75″ / 171.5mm
- Circumference
- 95.83″
- Revs/Mile
- 661
275/65R17
- Diameter
- 31.07″ / 789.3mm
- Section Width
- 10.83″
- Sidewall
- 7.04″ / 178.75mm
- Circumference
- 97.62″
- Revs/Mile
- 649
Speedometer & Diameter Impact
Wider tire — verify wheel widthAt an indicated 60 mph, your actual speed is 61.12 mph (98.37 km/h). Your speedometer reads 1.87% low versus actual speed.