Locate the full tire marking on the sidewall (example: 205/55R16 91V)
Identify the width in millimeters (first number before the slash, e.g., 205)
Identify the aspect ratio as a percentage of width (number after the slash, e.g., 55)
Identify the construction type (letter after aspect ratio, e.g., R = radial)
Identify the rim diameter in inches (number after the construction letter, e.g., 16)
Identify the load index (two- or three-digit number after the size, e.g., 91)
Identify the speed rating (letter after the load index, e.g., V)
Check the load range / additional load markings if present (e.g., LT, SL, XL, or load range letters/numbers)
Check tire type/usage marking (e.g., M+S, All Season, Winter, A/T, H/T, R/T, LT for light truck)
Check traction and temperature grades (e.g., Treadwear/Traction/Temperature: UTQG codes)
Check treadwear indicators (if present) and tire age code (DOT date code)
Read the DOT date code (last four digits: week and year, e.g., 2323 = week 23 of 2023)
Read rotation direction and mounting arrows (if the tire is directional)
Read “outside/inside” markings (if the tire is asymmetric)
Read maximum pressure and load limits (often near the tire size or on the sidewall; follow vehicle placard)
Check for additional symbols (e.g., snowflake/snow tire symbol for winter tires)
Confirm that the tire size matches the vehicle requirements (size, load index, and speed rating)
Verify compatibility with the vehicle’s recommended rim diameter and overall tire diameter range