285/40R20 Tire Size Specifications & Compatible Vehicles
Overall Diameter
736.0 mm
Section Width
285 mm
Sidewall Height
114.0 mm
Circumference
2312.2 mm
Revs/Mile
696
Rim Diameter
20"
Inch Equivalent
29x11.2R20
Rim Width (ETRTO)
8.5" – 11.0"
Alternative Tire Sizes
These tire sizes are within 3% overall diameter of 285/40R20 and may be used as replacements:
Popular Comparisons
See how 285/40R20 compares to other common tire sizes:
Understanding 285/40R20
The tire size 285/40R20 means the tire has a section width of 285mm, an aspect ratio of 40% (the sidewall height is 40% of the width), and fits a 20-inch rim.
Sidewall Height = 285 x 0.4 = 114.0 mm
Overall Diameter = (114.0 x 2) + (20 x 25.4) = 736.0 mm
Circumference = 736.0 x π = 2312.2 mm
Overall Diameter = (114.0 x 2) + (20 x 25.4) = 736.0 mm
Circumference = 736.0 x π = 2312.2 mm
Frequently Asked Questions
The 285/40R20 is a standard tire size. Check your vehicle door jamb sticker or owner manual to confirm compatibility.
A 285/40R20 tire has an overall diameter of 736.0mm (29.0 inches). The sidewall height is 114.0mm, and the total circumference is 2312mm.
For 285/40R20 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 285/40R20 736.0mm diameter. Compatible alternatives include 195/65R19, 225/45R21, 295/30R22. Use our Tire Size Calculator to compare any two sizes.