195/55R15 vs 205/55R15

205/55R15 is 0.43 in (11.0 mm) taller than 195/55R15, a +1.85% diameter difference. With the speedometer set for 195/55R15, an indicated 60 mph is 61.1 mph on 205/55R15.

Is this a safe swap?

Diameter difference +1.85%: within the ±3% guideline

By overall diameter alone, 205/55R15 falls inside the ±3% range commonly used as a guideline when replacing 195/55R15. 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.

195/55R15 vs 205/55R15 differences
Measurement	195/55R15	205/55R15	Difference	% diff
Overall diameter	23.44 in (595.5 mm)	23.88 in (606.5 mm)	+0.43 in (+11.0 mm)	+1.85%
Sidewall height	4.22 in (107.3 mm)	4.44 in (112.8 mm)	+0.22 in (+5.5 mm)	+5.13%
Section width	7.68 in (195.0 mm)	8.07 in (205.0 mm)	+0.39 in (+10.0 mm)	+5.13%
Circumference	73.65 in (1,870.8 mm)	75.01 in (1,905.4 mm)	+1.36 in (+34.6 mm)	+1.85%
Revolutions per mile	860	845	−16	−1.81%

True speed with the speedometer calibrated for 195/55R15
Indicated	Actual on 195/55R15	Actual on 205/55R15	Difference
30 mph	30.0 mph	30.6 mph	+0.6 mph
60 mph	60.0 mph	61.1 mph	+1.1 mph
75 mph	75.0 mph	76.4 mph	+1.4 mph

Ride-height change: 205/55R15 raises the vehicle by 0.22 in (5.5 mm) at the axle (half the +11.0 mm diameter difference).

205/55R15 is 0.43 in taller than 195/55R15 and 10 mm wider, a 1.85% difference in overall diameter.

With the speedometer calibrated for 195/55R15, an indicated 60 mph is actually 61.1 mph on 205/55R15, and revolutions per mile change from 860 to 845.

Both sizes mount on 15-inch wheels.

Size pages

Other comparisons with 195/55R15

Other comparisons with 205/55R15

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