The DOT or serial number begins with the letters "DOT" followed by a combination of numbers and letters up to 13 characters. You can find the DOT number on the sidewall of your tires as shown in the example. Do not include the letters "DOT" in the input box. Please note, when some tires are mounted, the full DOT number will face the inside of your wheel well and not show on the exterior facing sidewall. Your DOT code should be is 10-13 digits long with the last 4 digits as numbers.