245/55R18 Tire Size Specifications & Compatible Vehicles
Overall Diameter
726.7 mm
Section Width
245 mm
Sidewall Height
134.8 mm
Circumference
2283.0 mm
Revs/Mile
705
Rim Diameter
18"
Inch Equivalent
28.6x9.6R18
Rim Width (ETRTO)
7.0" – 9.0"
Alternative Tire Sizes
These tire sizes are within 3% overall diameter of 245/55R18 and may be used as replacements:
Understanding 245/55R18
The tire size 245/55R18 means the tire has a section width of 245mm, an aspect ratio of 55% (the sidewall height is 55% of the width), and fits a 18-inch rim.
Sidewall Height = 245 x 0.55 = 134.8 mm
Overall Diameter = (134.8 x 2) + (18 x 25.4) = 726.7 mm
Circumference = 726.7 x π = 2283.0 mm
Overall Diameter = (134.8 x 2) + (18 x 25.4) = 726.7 mm
Circumference = 726.7 x π = 2283.0 mm
Frequently Asked Questions
The 245/55R18 is a standard tire size. Check your vehicle door jamb sticker or owner manual to confirm compatibility.
A 245/55R18 tire has an overall diameter of 726.7mm (28.6 inches). The sidewall height is 134.8mm, and the total circumference is 2283mm.
For 245/55R18 tires, the ETRTO recommended rim width is 8.0". The acceptable range is 7.0" minimum to 9.0" maximum. Using a rim outside this range can cause improper bead seating and unsafe handling.
Yes, as long as the replacement tire overall diameter is within 3% of the 245/55R18 726.7mm diameter. Compatible alternatives include 295/50R17, 305/40R19, 225/60R18. Use our Tire Size Calculator to compare any two sizes.