225/55R18 tire size
A 225/55R18 tire stands 27.7 inches tall and 8.9 inches wide, with a 4.9-inch sidewall on an 18-inch rim.
- Overall height
- 27.7 in705 mm
- Section width
- 8.9 in225 mm
- Sidewall height
- 4.9 in124 mm
- Rim diameter
- 18 in457 mm
- Circumference
- 87.2 in2214 mm
- Revolutions per mile
- 727452 per km
- Inch size
- 27.7x8.9R18
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 225/55R18's overall height, the usual limit before the speedometer, ABS and transmission notice. The closest is 205/60R18, 0.2% shorter (0.06 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 225/55R18.
Other 18-inch sizes near 225/55R18
225 mm wide, other sidewalls
55 series, other widths
See the other sizes for this rim on 18-inch tire sizes.
Shop 225/55R18 tires
These open each store's own list of 225/55R18 tires, where you can filter by type, load and speed rating.
225/55R18 questions
How tall is a 225/55R18 tire?
About 27.7 inches (705 mm) from the ground to the top of the tread, unloaded. On the vehicle, carrying weight, it sits a little lower.
What does 225/55R18 mean?
225 is the section width in millimetres (8.9 in). 55 means the sidewall is 55% of that width: 124 mm, or 4.9 in. R means radial construction, and 18 is the rim diameter in inches.
Can I use 245/50R18 instead of 225/55R18?
245/50R18 is 0.4% shorter (0.10 in) and 20 mm wider, which is inside the usual 3% rule. With it fitted, the speedometer shows 60 mph when you are doing 59.8 mph. Make sure the extra width clears the suspension and fender liner at full lock.
What is 225/55R18 in inches?
In inch terms it is 27.7x8.9R18: 27.7 inches tall, 8.9 inches wide, for an 18-inch rim.
How many revolutions per mile does a 225/55R18 make?
About 727 turns per mile, worked out from its unloaded circumference of 87.2 inches. Makers list slightly higher numbers for their own tires, because a loaded tire rolls on a smaller radius.