305/45R22 tire size

A 305/45R22 tire is 32.81 inches (833.3 mm) tall, 12.01 in (305 mm) wide and fits a 22-inch wheel. In inch notation it is roughly a 32.8x12.0R22 — a "33-inch" tire.

305/45R22 dimensions
Overall diameter	32.81 in	833.3 mm
Section width	12.01 in	305 mm
Sidewall height	5.40 in	137.3 mm
Circumference	103.07 in	2,618 mm
Revolutions	614.7 per mile	382.0 per km
Rim diameter	22 in	558.8 mm

Compare 305/45R22 with another size

Current size

New size

Speed in mphkm/h

Overall diameter difference

+0.06%

60 mph on the speedometer = 60.0 mph actual

Within the ±3 % diameter range most tire fitters accept.

Ground clearance: +0.3 mm (+0.01 in)
Revolutions: 615 → 614 per mile

305/45R22 275/50R22

Side-by-side dimensions

	Current	New	Difference	%
Diameter	32.81 in	32.83 in	+0.02 in	+0.06%
Diameter	833.3 mm	833.8 mm	+0.5 mm	+0.06%
Width	12.01 in	10.83 in	−1.18 in	−9.84%
Width	305.0 mm	275.0 mm	−30.0 mm	−9.84%
Sidewall	5.40 in	5.41 in	+0.01 in	+0.18%
Sidewall	137.3 mm	137.5 mm	+0.3 mm	+0.18%
Circumference	103.07 in	103.13 in	+0.06 in	+0.06%
Revs per mile	614.7	614.4	−0.4	−0.06%

Speedometer error

Speedometer shows	Actual speed	Difference
20 mph	20.0 mph	0.0 mph
30 mph	30.0 mph	0.0 mph
40 mph	40.0 mph	0.0 mph
50 mph	50.0 mph	0.0 mph
60 mph	60.0 mph	0.0 mph
70 mph	70.0 mph	0.0 mph
80 mph	80.0 mph	0.0 mph

Alternative sizes on the same 22-inch wheel

Sizes in use within ±3 % of the overall diameter of 305/45R22:

Plus and minus sizes for 305/45R22

Size	Wheel	Diameter	Difference
275/60R20	Minus 2 (20 in)	32.99 in	+0.56%
305/55R20	Minus 2 (20 in)	33.21 in	+1.22%
285/55R20	Minus 2 (20 in)	32.34 in	−1.42%
285/60R20	Minus 2 (20 in)	33.46 in	+2.00%
275/50R21	Minus 1 (21 in)	31.83 in	−2.99%
285/40R23	Plus 1 (23 in)	31.98 in	−2.53%
325/35R23	Plus 1 (23 in)	31.96 in	−2.59%

Nearby 22-inch sizes

Reading the 305/45R22 size

305 — section width in millimetres (12.01 in).
45 — aspect ratio: the sidewall is 45 % of the width, 137.3 mm.
R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
22 — fits a 22-inch diameter wheel.

The load index and speed rating (for example 91V) follow the size on the sidewall. They must meet at least the values on your vehicle's tire placard.