TireSizesFinder

33x12.50R16 vs 305/65R17

305/65R17 is 0.39 in (9.9 mm) shorter than 33x12.50R16, a −1.18% diameter difference. With the speedometer set for 33x12.50R16, an indicated 60 mph is 59.3 mph on 305/65R17.

Is this a safe swap?

Diameter difference −1.18%: within the ±3% guideline

By overall diameter alone, 305/65R17 falls inside the ±3% range commonly used as a guideline when replacing 33x12.50R16. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 33x12.50R16 (33.00 in) vs 305/65R17 (32.61 in)33x12.50R1633.00 in × 12.50 in305/65R1732.61 in × 12.01 in
Side profile and tread width, drawn to the same scale.
33x12.50R16 vs 305/65R17 differences
Measurement33x12.50R16305/65R17Difference% diff
Overall diameter33.00 in (838.2 mm)32.61 in (828.3 mm)−0.39 in (−9.9 mm)−1.18%
Sidewall height8.50 in (215.9 mm)7.81 in (198.3 mm)−0.69 in (−17.7 mm)−8.18%
Section width12.50 in (317.5 mm)12.01 in (305.0 mm)−0.49 in (−12.5 mm)−3.94%
Circumference103.67 in (2,633.3 mm)102.45 in (2,602.2 mm)−1.22 in (−31.1 mm)−1.18%
Revolutions per mile611618+7+1.20%
True speed with the speedometer calibrated for 33x12.50R16
IndicatedActual on 33x12.50R16Actual on 305/65R17Difference
30 mph30.0 mph29.6 mph−0.4 mph
60 mph60.0 mph59.3 mph−0.7 mph
75 mph75.0 mph74.1 mph−0.9 mph

Ride-height change: 305/65R17 lowers the vehicle by 0.19 in (5.0 mm) at the axle (half the −9.9 mm diameter difference).

305/65R17 is 0.39 in shorter than 33x12.50R16 and 13 mm narrower, a 1.18% difference in overall diameter.

With the speedometer calibrated for 33x12.50R16, an indicated 60 mph is actually 59.3 mph on 305/65R17, and revolutions per mile change from 611 to 618.

305/65R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 33x12.50R16.

Size pages

Other comparisons with 33x12.50R16

Other comparisons with 305/65R17

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.