305/55R20 tire size
A 305/55R20 tire stands 33.2 inches tall and 12.0 inches wide, with a 6.6-inch sidewall on a 20-inch rim.
- Overall height
- 33.2 in844 mm
- Section width
- 12.0 in305 mm
- Sidewall height
- 6.6 in168 mm
- Rim diameter
- 20 in508 mm
- Circumference
- 104.3 in2650 mm
- Revolutions per mile
- 607377 per km
- Inch size
- 33.2x12.0R20
Compare it with any other size in the tire size calculator.
Sizes you can swap to
These 20-inch sizes are within two width steps and 3% of a 305/55R20's overall height, the usual limit before the speedometer, ABS and transmission notice. The closest is 285/60R20, 0.8% taller (0.26 in). Wider sizes also need room in the wheel well and a rim width that suits them.
Plus and minus sizes
Changing rim size means changing the sidewall to keep the same overall height. On 18-inch or 19-inch or 21-inch or 22-inch rims, these are the closest matches to a 305/55R20.
LT305/55R20
LT305/55R20 is the light-truck version of this size, with the same nominal height and width: 33.2 by 12.0 inches. LT tires have stiffer construction for heavier loads and towing, run at higher pressures and carry a load range (C, D, E or F) instead of a passenger load rating. Fit LT tires where the door placard calls for them or the truck works hard; on a light-duty vehicle they ride firmer than the P-metric size.
Other 20-inch sizes near 305/55R20
305 mm wide, other sidewalls
55 series, other widths
See the other sizes for this rim on 20-inch tire sizes, or other tires about this tall on 33-inch tires.
Shop 305/55R20 tires
These open each store's own list of 305/55R20 tires, where you can filter by type, load and speed rating.
305/55R20 questions
How tall is a 305/55R20 tire?
About 33.2 inches (844 mm) from the ground to the top of the tread, unloaded. On the vehicle, carrying weight, it sits a little lower.
What does 305/55R20 mean?
305 is the section width in millimetres (12.0 in). 55 means the sidewall is 55% of that width: 168 mm, or 6.6 in. R means radial construction, and 20 is the rim diameter in inches.
Is LT305/55R20 the same size as 305/55R20?
Yes, they share the same nominal size: 33.2 inches tall and 12.0 inches wide. The difference is construction. LT tires are built for heavier loads at higher pressures and carry a load range letter (C, D, E or F); they ride firmer than passenger tires.
Can I use 285/60R20 instead of 305/55R20?
285/60R20 is 0.8% taller (0.26 in) and 20 mm narrower, which is inside the usual 3% rule. With it fitted, the speedometer shows 60 mph when you are doing 60.5 mph.
What is 305/55R20 in inches?
In inch terms it is 33.2x12.0R20: 33.2 inches tall, 12.0 inches wide, for a 20-inch rim.
How many revolutions per mile does a 305/55R20 make?
About 607 turns per mile, worked out from its unloaded circumference of 104.3 inches. Makers list slightly higher numbers for their own tires, because a loaded tire rolls on a smaller radius.