tire date code UNRAVELED: What is it & why it matters

Tire Date Code Explained: What Is the Tire Date Code?

The tire date code is a critical piece of information that you can find embedded on the sidewall of a tire. This code indicates when the tire was manufactured and is an important piece of information to have.

It is part of the Department of Transportation (DOT) code, which is required on all tires sold in the United States. The tire DOT code is essentially an alphanumeric code (it has letters and numbers), that includes information about your tire manufacturing date, what size it is, a unique identifier, and when it was produced.

Knowing how to read this code can help you ensure that the tires that you are using are safe and reliable. The tire date code is typically located on the outer sidewall of the tire, near the rim.

What Does the DOT Code Consist of?

The DOT code consists of several components and each one of them provides some kind of information about the manufacturing of that specific tire.

Here is a breakdown of what the DOT code includes:

  • Plant Code: This is a two-letter or number-and-letter combination that identifies the manufacturing plant where the tire was produced. This code helps track the tire's origin and is essential in case of recalls.

  • Size Code: This series of digits and letters indicates the tire's size. It ensures the tire fits the intended vehicle and that it meets specific performance standards.

  • Optional Code: This part of the DOT code can include additional information such as the tire brand, model, or other manufacturer-specific data.

  • Date Code: The last four digits of the DOT code represent the week and year of manufacture. For example, if the code reads "1219," it means the tire was manufactured in the 12th week of 2019.

How To Read Tire Date Code Properly?

Reading the tire date code might seem confusing at first, but once you know what it is that you are looking for, it is actually quite easy. The date code is the last four digits of the DOT code, and it indicates the week and year the tire was manufactured.

Here’s how to decode it:

  • Find the DOT Code: Look for the "DOT" letters on the tire's sidewall, followed by a series of numbers and letters.

  • Locate the Last Four Digits: These digits represent the date code.

  • Decode the Week and Year: The first two digits of the date code indicate the week of the year (from 01 to 52), and the last two digits indicate the year.


For example, if the date code is "2319," the tire was manufactured in the 23rd week of 2019. Similarly, a code of "4507" means the tire was produced in the 45th week of 2007.

Why Is the Tire DOT Code Important?

The DOT code, particularly the tire date code, is crucial for several reasons. For all drivers on the road, it is important to ensure that your tires are in good shape and that they are well maintained. There are a number of different checks you can do to determine whether your tires are safe to use, but one thing you cannot tell with certainty (without looking at the DOT code), is just how old they are. Regardless of how much wear and tear the tires experience, there is a limit on the amount of time before they start to degrade.

Road Safety

The age of a tire significantly impacts its performance and safety. As tires get older, their rubber compounds break down which reduces their effectiveness in providing traction and handling. This degradation can lead to increased stopping distances, reduced grip, and a higher likelihood of blowouts.

Driving on old tires can be risky, especially in adverse weather conditions or at high speeds, as aged tires are more prone to failure.


Tire Manufacturing Date Laws & Regulations

The DOT code is a fundamental aspect of tire-related laws and regulations. It ensures that tires meet specific safety standards and allows for efficient tracking and recall processes if necessary.

Regulatory bodies like the National Highway Traffic Safety Administration (NHTSA) mandate that the tire date code be present on all tires to ensure they are safe for use and not past their useful life.

Factors That Affect Your Tires & Lead To Aging

There are a number of different things that can contribute to the aging of tires, it is not just about how many miles they have done (although this is obviously an important aspect as well). As tires age, so their safety and performance over time will diminish.

Environmental Factors

Certain environmental factors will have an adverse impact on the longevity of your tires. Extreme temperatures, for example, can accelerate the aging process of tires. High temperatures cause the rubber to break down more quickly, while very low temperatures can make the rubber brittle.

Prolonged exposure to ultraviolet (UV) rays from the sun is another environmental factor that causes tires to wear out as this will degrade the rubber compounds in tires, leading to cracks and weakening their structural integrity.

Storage Conditions

If you store your tires or car correctly, you could increase their useful life. Tires should be stored in a cool, dry place away from direct sunlight and any other sources of ozone, such as electrical motors. Improper storage can lead to premature aging, even if the tires are not in use.

Usage Factors

As we said above, usage is the one that most people think about when they think about their tires losing their integrity. For example, the more miles a tire travels, the more it wears out so regularly checking the tread depth can help determine when a tire needs to be replaced. Rough roads, potholes, and aggressive driving also have an impact as they can cause more wear and tear on tires. Additionally, frequent exposure to road salts and chemicals can accelerate the aging process.

How To Check for Tire Tear & Wear?

Regularly inspecting your tires for wear and tear is essential for maintaining safety and performance. Here are common ways to check:

  • Tread Depth: The tread of a tire refers to the grooves that run around the whole tire. Use a tread depth gauge to measure the depth of the grooves. Tires with a tread depth below 2/32 of an inch are considered unsafe.

  • Visual Inspection: Look for cracks, bulges, or cuts on the tire sidewalls and tread. These can indicate structural damage.

  • Uneven Wear: Check for uneven wear patterns, which can suggest alignment or suspension issues.


Regular tire inspections help identify potential issues early, preventing unexpected tire failures and maintaining optimal vehicle performance.

Should Every Driver Know How To Check the Tire Date Code?

Absolutely! Every driver should know how to read tire date code/dot code. Understanding how to read this code helps drivers determine when their tires are too old and need replacement. By regularly checking the tire date code and ensuring that tires are not older than six years, you can enhance safety, improve vehicle performance, and reduce the risk of accidents caused by tire failures.

The tire date code is an essential piece of information that every driver should definitely be familiar with. It helps ensure that tires are safe to use and comply with safety regulations. By understanding and regularly checking the tire date code, drivers can maintain their vehicles' safety and performance on the road.

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