285/45R20 Tire Size Specifications & Compatible Vehicles
Overall Diameter
764.5 mm
Section Width
285 mm
Sidewall Height
128.3 mm
Circumference
2401.7 mm
Revs/Mile
670
Rim Diameter
20"
Inch Equivalent
30.1x11.2R20
Rim Width (ETRTO)
8.5" – 11.0"
Alternative Tire Sizes
These tire sizes are within 3% overall diameter of 285/45R20 and may be used as replacements:
Understanding 285/45R20
The tire size 285/45R20 means the tire has a section width of 285mm, an aspect ratio of 45% (the sidewall height is 45% of the width), and fits a 20-inch rim.
Sidewall Height = 285 x 0.45 = 128.3 mm
Overall Diameter = (128.3 x 2) + (20 x 25.4) = 764.5 mm
Circumference = 764.5 x π = 2401.7 mm
Overall Diameter = (128.3 x 2) + (20 x 25.4) = 764.5 mm
Circumference = 764.5 x π = 2401.7 mm
Frequently Asked Questions
The 285/45R20 is a standard tire size. Check your vehicle door jamb sticker or owner manual to confirm compatibility.
A 285/45R20 tire has an overall diameter of 764.5mm (30.1 inches). The sidewall height is 128.3mm, and the total circumference is 2402mm.
For 285/45R20 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 285/45R20 764.5mm diameter. Compatible alternatives include 235/60R19, 165/70R21, 205/75R18. Use our Tire Size Calculator to compare any two sizes.