TireSizesFinder

30x9.50R15 vs 235/75R16

235/75R16 is 0.12 in (3.1 mm) shorter than 30x9.50R15, a −0.41% diameter difference. With the speedometer set for 30x9.50R15, an indicated 60 mph is 59.8 mph on 235/75R16.

Is this a safe swap?

Diameter difference −0.41%: under 1%

By overall diameter alone, 235/75R16 is a near match for 30x9.50R15; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 30x9.50R15 (30.00 in) vs 235/75R16 (29.88 in)30x9.50R1530.00 in × 9.50 in235/75R1629.88 in × 9.25 in
Side profile and tread width, drawn to the same scale.
30x9.50R15 vs 235/75R16 differences
Measurement30x9.50R15235/75R16Difference% diff
Overall diameter30.00 in (762.0 mm)29.88 in (758.9 mm)−0.12 in (−3.1 mm)−0.41%
Sidewall height7.50 in (190.5 mm)6.94 in (176.3 mm)−0.56 in (−14.2 mm)−7.48%
Section width9.50 in (241.3 mm)9.25 in (235.0 mm)−0.25 in (−6.3 mm)−2.61%
Circumference94.25 in (2,393.9 mm)93.86 in (2,384.2 mm)−0.38 in (−9.7 mm)−0.41%
Revolutions per mile672675+3+0.41%
True speed with the speedometer calibrated for 30x9.50R15
IndicatedActual on 30x9.50R15Actual on 235/75R16Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.8 mph−0.2 mph
75 mph75.0 mph74.7 mph−0.3 mph

Ride-height change: 235/75R16 lowers the vehicle by 0.06 in (1.6 mm) at the axle (half the −3.1 mm diameter difference).

235/75R16 is 0.12 in shorter than 30x9.50R15 and 6 mm narrower, a 0.41% difference in overall diameter.

With the speedometer calibrated for 30x9.50R15, an indicated 60 mph is actually 59.8 mph on 235/75R16, and revolutions per mile change from 672 to 675.

235/75R16 mounts on a 16-inch wheel, a plus-1 fitment from the 15-inch wheel of 30x9.50R15.

Size pages

Other comparisons with 30x9.50R15

Other comparisons with 235/75R16

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