325/35R20 tire size

A 325/35R20 tire is 28.96 inches (735.5 mm) tall, 12.80 in (325 mm) wide and fits a 20-inch wheel. In inch notation it is roughly a 29.0x12.8R20 — a "29-inch" tire.

325/35R20 dimensions
Overall diameter28.96 in735.5 mm
Section width12.80 in325 mm
Sidewall height4.48 in113.8 mm
Circumference90.97 in2,311 mm
Revolutions696.5 per mile432.8 per km
Rim diameter20 in508.0 mm

Compare 325/35R20 with another size

Speed in

Overall diameter difference

−0.95%

60 mph on the speedometer = 59.4 mph actual

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

Ground clearance
−3.5 mm (−0.14 in)
Revolutions
696 → 703 per mile

325/35R20 315/35R20

Side-by-side dimensions

CurrentNewDifference%
Diameter28.96 in28.68 in−0.28 in−0.95%
Diameter735.5 mm728.5 mm−7.0 mm−0.95%
Width12.80 in12.40 in−0.39 in−3.08%
Width325.0 mm315.0 mm−10.0 mm−3.08%
Sidewall4.48 in4.34 in−0.14 in−3.08%
Sidewall113.8 mm110.3 mm−3.5 mm−3.08%
Circumference90.97 in90.10 in−0.87 in−0.95%
Revs per mile696.5 703.2 +6.7 +0.96%

Speedometer error

Speedometer showsActual speedDifference
20 mph19.8 mph−0.2 mph
30 mph29.7 mph−0.3 mph
40 mph39.6 mph−0.4 mph
50 mph49.5 mph−0.5 mph
60 mph59.4 mph−0.6 mph
70 mph69.3 mph−0.7 mph
80 mph79.2 mph−0.8 mph

Alternative sizes on the same 20-inch wheel

Sizes in use within ±3 % of the overall diameter of 325/35R20:

Plus and minus sizes for 325/35R20

SizeWheelDiameterDifference
345/35R19Minus 1 (19 in)28.51 in−1.55%
295/45R19Minus 1 (19 in)29.45 in+1.71%
295/40R19Minus 1 (19 in)28.29 in−2.30%
335/30R21Plus 1 (21 in)28.91 in−0.15%
295/35R21Plus 1 (21 in)29.13 in+0.60%
345/30R21Plus 1 (21 in)29.15 in+0.67%
325/30R21Plus 1 (21 in)28.68 in−0.97%
295/30R22Plus 2 (22 in)28.97 in+0.04%
355/25R22Plus 2 (22 in)28.99 in+0.11%
305/30R22Plus 2 (22 in)29.20 in+0.86%
315/30R22Plus 2 (22 in)29.44 in+1.67%

Nearby 20-inch sizes

Reading the 325/35R20 size

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.