305/70R18 tire size
A 305/70R18 tire stands 34.8 inches tall and 12.0 inches wide, with a 8.4-inch sidewall on an 18-inch rim.
- Overall height
- 34.8 in884 mm
- Section width
- 12.0 in305 mm
- Sidewall height
- 8.4 in214 mm
- Rim diameter
- 18 in457 mm
- Circumference
- 109.4 in2778 mm
- Revolutions per mile
- 579360 per km
- Inch size
- 34.8x12.0R18
Compare it with any other size in the tire size calculator.
Sizes you can swap to
These 18-inch sizes are within two width steps and 3% of a 305/70R18's overall height, the usual limit before the speedometer, ABS and transmission notice. The closest is 285/75R18, 0.1% taller (0.02 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 16-inch or 17-inch or 19-inch or 20-inch rims, these are the closest matches to a 305/70R18.
LT305/70R18
LT305/70R18 is the light-truck version of this size, with the same nominal height and width: 34.8 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 18-inch sizes near 305/70R18
305 mm wide, other sidewalls
70 series, other widths
See the other sizes for this rim on 18-inch tire sizes, or other tires about this tall on 35-inch tires.
Shop 305/70R18 tires
These open each store's own list of 305/70R18 tires, where you can filter by type, load and speed rating.
305/70R18 questions
How tall is a 305/70R18 tire?
About 34.8 inches (884 mm) from the ground to the top of the tread, unloaded. On the vehicle, carrying weight, it sits a little lower.
What does 305/70R18 mean?
305 is the section width in millimetres (12.0 in). 70 means the sidewall is 70% of that width: 214 mm, or 8.4 in. R means radial construction, and 18 is the rim diameter in inches.
Is LT305/70R18 the same size as 305/70R18?
Yes, they share the same nominal size: 34.8 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 285/75R18 instead of 305/70R18?
285/75R18 is 0.1% taller (0.02 in) and 20 mm narrower, which is inside the usual 3% rule. With it fitted, the speedometer shows 60 mph when you are doing 60.0 mph.
What is 305/70R18 in inches?
In inch terms it is 34.8x12.0R18: 34.8 inches tall, 12.0 inches wide, for an 18-inch rim.
How many revolutions per mile does a 305/70R18 make?
About 579 turns per mile, worked out from its unloaded circumference of 109.4 inches. Makers list slightly higher numbers for their own tires, because a loaded tire rolls on a smaller radius.