205/70R14 vs 205/65R15

205/65R15 is 0.19 in (4.9 mm) taller than 205/70R14, a +0.76% diameter difference. With the speedometer set for 205/70R14, an indicated 60 mph is 60.5 mph on 205/65R15.

Is this a safe swap?

Diameter difference +0.76%: under 1%

By overall diameter alone, 205/65R15 is a near match for 205/70R14; the speedometer changes by less than 1%. 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.

205/70R14 vs 205/65R15 differences
Measurement	205/70R14	205/65R15	Difference	% diff
Overall diameter	25.30 in (642.6 mm)	25.49 in (647.5 mm)	+0.19 in (+4.9 mm)	+0.76%
Sidewall height	5.65 in (143.5 mm)	5.25 in (133.3 mm)	−0.40 in (−10.2 mm)	−7.14%
Section width	8.07 in (205.0 mm)	8.07 in (205.0 mm)	0.00 in (0.0 mm)	0.00%
Circumference	79.48 in (2,018.8 mm)	80.09 in (2,034.2 mm)	+0.61 in (+15.4 mm)	+0.76%
Revolutions per mile	797	791	−6	−0.76%

True speed with the speedometer calibrated for 205/70R14
Indicated	Actual on 205/70R14	Actual on 205/65R15	Difference
30 mph	30.0 mph	30.2 mph	+0.2 mph
60 mph	60.0 mph	60.5 mph	+0.5 mph
75 mph	75.0 mph	75.6 mph	+0.6 mph

Ride-height change: 205/65R15 raises the vehicle by 0.10 in (2.5 mm) at the axle (half the +4.9 mm diameter difference).

205/65R15 is 0.19 in taller than 205/70R14 and the same width, a 0.76% difference in overall diameter.

With the speedometer calibrated for 205/70R14, an indicated 60 mph is actually 60.5 mph on 205/65R15, and revolutions per mile change from 797 to 791.

205/65R15 mounts on a 15-inch wheel, a plus-1 fitment from the 14-inch wheel of 205/70R14.

Size pages

Other comparisons with 205/70R14

Other comparisons with 205/65R15

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