275/70R17 vs 33x12.50R17

33x12.50R17 is 0.84 in (21.4 mm) taller than 275/70R17, a +2.62% diameter difference. With the speedometer set for 275/70R17, an indicated 60 mph is 61.6 mph on 33x12.50R17.

Is this a safe swap?

Diameter difference +2.62%: within the ±3% guideline

By overall diameter alone, 33x12.50R17 falls inside the ±3% range commonly used as a guideline when replacing 275/70R17. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

275/70R17 vs 33x12.50R17 differences
Measurement	275/70R17	33x12.50R17	Difference	% diff
Overall diameter	32.16 in (816.8 mm)	33.00 in (838.2 mm)	+0.84 in (+21.4 mm)	+2.62%
Sidewall height	7.58 in (192.5 mm)	8.00 in (203.2 mm)	+0.42 in (+10.7 mm)	+5.56%
Section width	10.83 in (275.0 mm)	12.50 in (317.5 mm)	+1.67 in (+42.5 mm)	+15.45%
Circumference	101.03 in (2,566.1 mm)	103.67 in (2,633.3 mm)	+2.65 in (+67.2 mm)	+2.62%
Revolutions per mile	627	611	−16	−2.55%

True speed with the speedometer calibrated for 275/70R17
Indicated	Actual on 275/70R17	Actual on 33x12.50R17	Difference
30 mph	30.0 mph	30.8 mph	+0.8 mph
60 mph	60.0 mph	61.6 mph	+1.6 mph
75 mph	75.0 mph	77.0 mph	+2.0 mph

Ride-height change: 33x12.50R17 raises the vehicle by 0.42 in (10.7 mm) at the axle (half the +21.4 mm diameter difference).

33x12.50R17 is 0.84 in taller than 275/70R17 and 43 mm wider, a 2.62% difference in overall diameter.

With the speedometer calibrated for 275/70R17, an indicated 60 mph is actually 61.6 mph on 33x12.50R17, and revolutions per mile change from 627 to 611.

Both sizes mount on 17-inch wheels.

Size pages

Other comparisons with 275/70R17

Other comparisons with 33x12.50R17

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.