How to Read a Tire Date Code

Every tire sold in the United States carries a date code stamped right into the rubber. It tells you exactly when that tire was manufactured, down to the week. Yet most drivers have never looked at it, and plenty of tire shops never mention it. Knowing how to read this code takes about thirty seconds to learn and could keep you from driving on tires that are too old to be safe.

I check the date code on every tire that comes through my shop, whether it is on a vehicle for service or sitting on a rack waiting to be sold. It is one of the fastest and most reliable safety checks you can do, and it costs nothing but a quick look at the sidewall.

Where Do You Find the DOT Code?

Look at the sidewall of your tire, the flat area between the tread and the wheel rim. You are looking for the letters "DOT" followed by a string of characters. This is the Department of Transportation identification code, and every tire sold in the U.S. must have one.

The full DOT code contains information about the manufacturing plant, tire size, and other specifications. The part you care about is at the very end: the last four digits. These four numbers are your date code.

Here is the catch that trips people up. The complete DOT code with all four date digits is sometimes only stamped on one side of the tire. If you look at the outward-facing sidewall and see the DOT letters followed by only a partial code, walk around to the inward-facing side. The full code with the date is usually on the side that faces the vehicle. On some tires, you may need to crouch down or use a flashlight to read it clearly.

How Do You Decode the Four-Digit Date?

The system is straightforward. The first two digits represent the week of manufacture, and the second two digits represent the year. There are 52 weeks in a year, so the week number will be between 01 and 52.

Here are a few examples:

• 2519 means the tire was made in the 25th week of 2019, which is around late June 2019.
• 0823 means the tire was made in the 8th week of 2023, which is around late February 2023.
• 4721 means the tire was made in the 47th week of 2021, which is around late November 2021.

You do not need to memorize a conversion chart. Just remember: first two numbers are the week, last two numbers are the year. That is all there is to it.

What If the Code Has Only Three Digits?

Before the year 2000, tire date codes used a three-digit format. The first two digits were the week, and the single last digit was the year. The problem is that a code like 258 could mean the 25th week of 1988 or the 25th week of 1998. There is no way to tell the decade apart.

If you find a tire with a three-digit date code, it is at least 25 years old. Replace it immediately. There is no scenario where a tire from the 1990s or earlier is safe to drive on, regardless of how the tread looks. The rubber compounds have long since degraded past their useful life.

Why Does the Manufacturing Date Matter?

Rubber is an organic material that breaks down over time. From the moment a tire is made, oxygen slowly works into the rubber and breaks down its chemical bonds. This process, called oxidation, makes the rubber harder and more brittle. UV light and heat speed it up. Even a tire sitting in a cool, dark warehouse will eventually degrade.

The practical result is that an old tire loses grip, becomes more prone to cracking, and is at greater risk of catastrophic failure. The internal layers can separate. The sidewall can develop bulges or weak spots. A tire that looks perfectly fine on the outside can be falling apart on the inside.

This is why tire age matters alongside tread depth. You can have a tire with 8/32 of tread that is still dangerous because it is eight years old. The date code is the only way to know for sure. For additional guidance on age-related tire safety, the tires.org resource is worth reviewing.

When Should You Replace a Tire Based on Age?

The general industry guideline is:

• Under 5 years: The tire is within its normal service life. Focus on tread depth and condition.
• 5 to 6 years: Have the tires inspected by a professional annually. Look for cracking in the sidewall and tread grooves.
• 6 to 10 years: Most manufacturers recommend replacement in this window, even if tread depth is adequate.
• Over 10 years: Replace the tire regardless of condition. No exceptions.

These guidelines apply to all tires, including spare tires. Your spare has been aging in the trunk or under the vehicle this whole time. If your car is nine years old and still has the original spare, that spare is nine years old too.

How Does the Date Code Apply to Used Tires?

This is where the date code becomes especially important. When you buy used tires, you are often getting tires with unknown history. The seller may know the tread depth but not the age. Or they may not mention the age on purpose.

Always check the date code before buying a used tire. A tire with 7/32 of tread sounds like a good deal until you realize it was manufactured in 2016. That tire is already past the recommended inspection window and approaching the hard replacement deadline. You would be paying for tread life you may never safely use.

Reputable used tire dealers will check and disclose the date code. If a seller cannot or will not tell you the manufacturing date, walk away. There are plenty of reasons a used tire might be unsafe to sell, and age is one of the most common.

How Should You Record and Track Tire Age?

When you buy new tires, write down the DOT date codes and keep them with your vehicle records. You can also take a photo of each tire's sidewall code with your phone. This way, you do not have to crawl under the car every time you want to check the age.

If you rotate your tires regularly (and you should), the position will change but the date code stays the same. All four tires on most vehicles are the same age unless one was replaced individually due to damage.

Make a habit of checking the date code during your monthly tire inspection, alongside checking for wear patterns and correct inflation. It takes an extra few seconds and gives you one more piece of information about whether your tires are still safe for the road.