185/75R15 Tire Size Specifications & Compatible Vehicles
Overall Diameter
658.5 mm
Section Width
185 mm
Sidewall Height
138.8 mm
Circumference
2068.7 mm
Revs/Mile
778
Rim Diameter
15"
Inch Equivalent
25.9x7.3R15
Rim Width (ETRTO)
5.0" – 7.0"
Alternative Tire Sizes
These tire sizes are within 3% overall diameter of 185/75R15 and may be used as replacements:
Understanding 185/75R15
The tire size 185/75R15 means the tire has a section width of 185mm, an aspect ratio of 75% (the sidewall height is 75% of the width), and fits a 15-inch rim.
Sidewall Height = 185 x 0.75 = 138.8 mm
Overall Diameter = (138.8 x 2) + (15 x 25.4) = 658.5 mm
Circumference = 658.5 x π = 2068.7 mm
Overall Diameter = (138.8 x 2) + (15 x 25.4) = 658.5 mm
Circumference = 658.5 x π = 2068.7 mm
Frequently Asked Questions
The 185/75R15 is a standard tire size. Check your vehicle door jamb sticker or owner manual to confirm compatibility.
A 185/75R15 tire has an overall diameter of 658.5mm (25.9 inches). The sidewall height is 138.8mm, and the total circumference is 2069mm.
For 185/75R15 tires, the ETRTO recommended rim width is 6.0". The acceptable range is 5.0" minimum to 7.0" 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 185/75R15 658.5mm diameter. Compatible alternatives include 315/40R16, 275/55R14, 175/65R17. Use our Tire Size Calculator to compare any two sizes.