DOT Code Explained: Complete Guide to Understanding DOT Tire Codes

The DOT code on your tire contains important information. This comprehensive guide explains everything you need to know about DOT codes, what they mean, and why they matter.

What is a DOT Code?

DOT stands for Department of Transportation. A DOT code is a unique identification number stamped on every tire sold in the United States. This code is mandated by the National Highway Traffic Safety Administration (NHTSA) and provides important information about the tire's manufacturing details.

📋 Key Points:

  • Required by law on all tires sold in the U.S.
  • Contains manufacturing plant code and production date
  • Helps track tires for recalls and safety issues
  • Essential for determining tire age

Parts of a DOT Code

A complete DOT code consists of several parts. Let's break down an example:

DOT ABCD EF 4523

DOT Prefix

The letters "DOT" indicate that the tire complies with U.S. Department of Transportation safety standards.

Note: Some tires may not have the "DOT" prefix, but the code structure remains the same.

Plant Code

The letters following "DOT" (e.g., "ABCD") identify the manufacturing plant where the tire was produced. This helps in tracking and quality control.

  • Typically 2-4 characters
  • Unique to each manufacturing facility
  • Used for recall purposes

Optional Codes

Some DOT codes include additional letters (e.g., "EF") that provide extra manufacturer-specific information.

Production Date Code

The last 4 digits are the most important part: they indicate when the tire was manufactured.

  • First 2 digits: Week of the year (01-52)
  • Last 2 digits: Year (last 2 digits)
  • Example: "4523" = Week 45 of 2023

Why DOT Codes Are Important

🛡️

Safety

Knowing tire age helps determine when tires should be replaced for safety reasons, regardless of tread depth.

🔍

Recalls

DOT codes help identify tires affected by recalls and safety notices from manufacturers or NHTSA.

💼

Warranty Claims

Tire warranties often require DOT codes for claims. It proves when the tire was manufactured.

📊

Quality Tracking

Manufacturers use DOT codes to track production quality and identify issues in specific batches.

How to Read DOT Codes

Example: DOT ABCD 4523

DOT

DOT Prefix

Department of Transportation identifier

ABCD

Plant Code

Manufacturing facility identifier

45

Week 45

Week of the year (1-52)

23

Year 2023

Last 2 digits of the year

3-Digit vs 4-Digit Date Codes

4-Digit Code (Modern)

4523

Used since 2000. First 2 digits = week, last 2 digits = year.

Example: 4523 = Week 45, Year 2023

3-Digit Code (Pre-2000)

453

Used before 2000. First 2 digits = week, last digit = year (0-9 = 1990-1999).

Warning: 3-digit codes indicate tires over 20 years old!

Decode Your DOT Code Instantly

Use our free DOT code decoder tool to instantly understand your tire's manufacturing information and production date.

Decode DOT Code Now →