Tire Size Conversion
275/65r18 to inches
Precise conversion of tire size 275/65r18: section width, sidewall height, overall diameter, circumference, and revolutions per mile. Includes exact mm ↔ inches results and quick guidance.
Section width
275 mm
10.83 inches
Sidewall height
178.8 mm
7.04" (65% of width)
Wheel (rim) diameter
18"
457.2 mm
Overall diameter
32.07"
814.7 mm
Circumference
100.77"
2559.5 mm
Revolutions per mile/km
629 revs/mile
391 revs/km
About 275/65r18 tire size
The size 275/65r18 indicates a section width of 275 mm (10.83 inches), an aspect ratio of 65% (sidewall height 178.8 mm or 7.04 inches), and a 18-inch wheel. Overall diameter calculates to 32.07 inches (814.7 mm), with circumference 100.77 inches.
Use these measurements to estimate speedometer error and clearance changes when switching sizes. For multi-size comparison and speed error calculation, try our dedicated tire size calculator.
Common tire sizes
Compare 275/65r18 with other popular tire sizes to find the perfect fit for your vehicle.