The code on the side of automobile tire provides a information about the tire and its construction.

Examble: P145/65R15 95H




initial letter(s)

P indicates P-metric for the United States; LT for light truck; no letter indicates Euro metric; ST for special trailer; T for temporary spare tire

3 digit number before /

tire width in mm

2 digit number after /

aspect ratio (ratio of height to width in mm) as percent


carcass construction (R radial; B bias belt; D diagonal; none indicates cross-ply tire)

1 or 2 digit number

rim diameter in inches

2 or 3 digit number

load index


speed rating


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