215/75R16 vs 255/65R16

255/65R16 is 0.35 in (9.0 mm) taller than 215/75R16, a +1.23% diameter difference. With the speedometer set for 215/75R16, an indicated 60 mph is 60.7 mph on 255/65R16.

Is this a safe swap?

Diameter difference +1.23%: within the ±3% guideline

By overall diameter alone, 255/65R16 falls inside the ±3% range commonly used as a guideline when replacing 215/75R16. 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.

215/75R16 vs 255/65R16 differences
Measurement	215/75R16	255/65R16	Difference	% diff
Overall diameter	28.70 in (728.9 mm)	29.05 in (737.9 mm)	+0.35 in (+9.0 mm)	+1.23%
Sidewall height	6.35 in (161.3 mm)	6.53 in (165.8 mm)	+0.18 in (+4.5 mm)	+2.79%
Section width	8.46 in (215.0 mm)	10.04 in (255.0 mm)	+1.57 in (+40.0 mm)	+18.60%
Circumference	90.15 in (2,289.9 mm)	91.27 in (2,318.2 mm)	+1.11 in (+28.3 mm)	+1.23%
Revolutions per mile	703	694	−9	−1.22%

True speed with the speedometer calibrated for 215/75R16
Indicated	Actual on 215/75R16	Actual on 255/65R16	Difference
30 mph	30.0 mph	30.4 mph	+0.4 mph
60 mph	60.0 mph	60.7 mph	+0.7 mph
75 mph	75.0 mph	75.9 mph	+0.9 mph

Ride-height change: 255/65R16 raises the vehicle by 0.18 in (4.5 mm) at the axle (half the +9.0 mm diameter difference).

255/65R16 is 0.35 in taller than 215/75R16 and 40 mm wider, a 1.23% difference in overall diameter.

With the speedometer calibrated for 215/75R16, an indicated 60 mph is actually 60.7 mph on 255/65R16, and revolutions per mile change from 703 to 694.

Both sizes mount on 16-inch wheels.

Size pages

Other comparisons with 215/75R16

Other comparisons with 255/65R16

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