275/55R18 Tire Size Specifications & Compatible Vehicles
Overall Diameter
759.7 mm
Section Width
275 mm
Sidewall Height
151.3 mm
Circumference
2386.7 mm
Revs/Mile
674
Rim Diameter
18"
Inch Equivalent
29.9x10.8R18
Rim Width (ETRTO)
8.5" – 11.0"
Alternative Tire Sizes
These tire sizes are within 3% overall diameter of 275/55R18 and may be used as replacements:
Understanding 275/55R18
The tire size 275/55R18 means the tire has a section width of 275mm, an aspect ratio of 55% (the sidewall height is 55% of the width), and fits a 18-inch rim.
Sidewall Height = 275 x 0.55 = 151.3 mm
Overall Diameter = (151.3 x 2) + (18 x 25.4) = 759.7 mm
Circumference = 759.7 x π = 2386.7 mm
Overall Diameter = (151.3 x 2) + (18 x 25.4) = 759.7 mm
Circumference = 759.7 x π = 2386.7 mm
Frequently Asked Questions
The 275/55R18 is a standard tire size. Check your vehicle door jamb sticker or owner manual to confirm compatibility.
A 275/55R18 tire has an overall diameter of 759.7mm (29.9 inches). The sidewall height is 151.3mm, and the total circumference is 2387mm.
For 275/55R18 tires, the ETRTO recommended rim width is 9.5". The acceptable range is 8.5" minimum to 11.0" 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 275/55R18 759.7mm diameter. Compatible alternatives include 205/80R17, 315/40R20, 185/75R19. Use our Tire Size Calculator to compare any two sizes.