ElpiAuto245/75R16 vs 305/70R16
305/70R16 is 2.34″ (60 mm) taller than 245/75R16, a 7.7% difference in overall diameter — outside the ±3% band, so expect the speedometer to drift and check for rubbing before fitting.
| Measurement | 245/75R16 | 305/70R16 | Difference | % |
|---|---|---|---|---|
| Overall diameter | 30.47″ | 32.81″ | +2.34″ | +7.7% |
| Section width | 9.65″ | 12.01″ | +2.36″ | +24.5% |
| Sidewall height | 7.23″ | 8.41″ | +1.17″ | +16.2% |
| Circumference | 95.72″ | 103.08″ | +7.36″ | +7.7% |
| Revs per mile | 661.9 | 614.7 | −47.3 | −7.1% |
| Revs per km | 411.3 | 381.9 | −29.4 | −7.1% |
Speedometer: with 245/75R16 as the original, 305/70R16 makes an indicated 60 mph really about 64.6 mph, and the axle sits ~1.17″ higher.
Reading this comparison
The overall diameter is what matters here: 305/70R16 is the taller tire. It sets ride height, gearing and how far the tire travels per revolution — which is what the speedometer and odometer count. Width and sidewall change fit and feel (a wider tire needs a wider wheel and more clearance; a shorter sidewall sharpens steering) but not the gearing.
Figures are geometric estimates from the size codes; real moulded tires vary by brand by 1–3%. Confirm load rating, wheel width and physical clearance on your vehicle before fitting. To compare any other two sizes, use the tire size comparison tool; to decode one size and see what else fits its wheel, the tire size calculator.