How To Tell When Tire Was Made | Decode Sidewall Date

A tire’s age appears in the last four digits of its DOT code: the first two show the week, and the last two show the year.

If you’re checking a used car, buying tires, or sizing up an old spare, the date matters. It is tucked into the DOT code on the sidewall, not printed as a plain month and year.

Once you know where to find that code, reading it takes less than a minute. You only need the date block at the end of the full DOT Tire Identification Number, often called the TIN.

How To Tell When Tire Was Made On Any Sidewall

Start by finding the letters “DOT” on the tire sidewall. That marks the Tire Identification Number used in the United States. After those letters, you’ll see a mix of letters and numbers. The date is the last four digits of the full code on tires made in 2000 or later.

Use this quick method:

• Find the sidewall that shows the full DOT code, not the shortened version.
• Read all the way to the end of that code.
• Take the last four digits only.
• Split them into two pairs: week first, year second.

Read The Last Four Digits

The first two digits show the production week. The last two show the production year. If the code ends in 2319, the tire was made in the 23rd week of 2019. If it ends in 4022, it was made in the 40th week of 2022.

This is the part most drivers need. The rest of the DOT string tracks the plant and other maker details, which you do not need when your goal is the build date.

What A Three-Digit Date Code Means

If you find a tire with a three-digit date code, you’re dealing with a tire made before 2000. That old format used two digits for the week and one for the year within the decade. A tire old enough to carry that format is far past normal road-use age, even if the tread still looks decent.

Old spares and trailer tires catch people off guard for that reason. They can sit for years, show low wear, and still be much older than they seem.

Marks That Matter And Marks That Do Not

A lot of numbers live on a tire. Only one group gives you the manufacture date. Tire size, load index, speed rating, UTQG grades, and the maximum pressure line do not tell you when the tire was built.

Drivers also mix up the build date with the day the tire was bought or installed. A tire can sit in inventory before it reaches a shop, so the clock started before it touched your car.

Here’s another easy mistake: reading the last four digits you spot anywhere on the sidewall. The date must be the last four digits of the full DOT code. If the sidewall only shows a partial TIN, switch to the other side of the tire and check again.

When The Full DOT Code Is Hard To Find

Some tires show the full TIN on one sidewall and a shorter version on the other. The full code may face inward, so you might need to turn the steering wheel or use a flashlight.

The USTMA tire facts page spells out that the TIN starts with “DOT” and that the last four digits give the week and year for tires made in 2000 or later. NHTSA’s tire buyers’ FAQ also notes that the date may not be visible on both sides of the tire, so checking both sidewalls is part of the job.

Step By Step In Your Driveway

1. Park on level ground and turn the wheel outward if you’re checking a front tire.
2. Find the letters “DOT.”
3. Read to the last four digits of the full code.
4. Take a photo so you can compare all four tires later.
5. Repeat on each tire, including the spare if your car has one.

That last step matters more than people think. It is common to find one tire that was replaced after a puncture or curb hit. Mixed date codes do not always mean trouble, but they do tell you the set has a story.

DOT Ending	Build Date	What It Tells You
0124	Week 1 of 2024	Built right at the start of 2024.
0823	Week 8 of 2023	Made in late winter 2023.
2319	Week 23 of 2019	Built around early summer 2019.
4022	Week 40 of 2022	Made near early fall 2022.
5118	Week 51 of 2018	Built near the end of 2018.
0309	Week 3 of 2009	An older tire even if it still has tread left.
5216	Week 52 of 2016	Made in the final week of that year.
1521	Week 15 of 2021	Built in spring 2021.

What Tire Age Tells You And What It Does Not

The build date tells you how old the tire is. It does not tell you how healthy the tire is today. Storage, heat, inflation habits, road damage, repairs, and long periods of sitting shape what the tire is like right now.

An older tire with deep tread can still deserve a hard second thought, while a newer tire with bad wear or sidewall damage can be ready for replacement early. You need both the date and a plain visual check.

When you’re checking the tire after reading the code, scan for:

• Cracks in the sidewall or between tread blocks
• Bulges, bubbles, or deep cuts
• Uneven wear across the tread
• Repeated air loss
• Vibration that started after a pothole or impact

Check Item	Where To Find It	Why It Matters
DOT date code	End of the full DOT/TIN on the sidewall	Shows the tire’s production week and year.
Tread depth and wear bars	Main tread grooves	Shows how much usable tread remains.
Cracking	Sidewall and tread grooves	Can point to aging or dry rot.
Bulges or bubbles	Sidewall	Can mean internal tire damage.
Patch or repair history	Inside tread area if removed; shop records	Helps you judge the tire as a whole, not by age alone.

How To Compare Tires On A Used Car Or At A Shop

If you’re buying a used car, read all four date codes before shiny tread grabs your eye. A set with close build dates often means the tires were bought together. One tire from last year and another from five years ago calls for better questions.

At a tire shop, ask the staff to show you the DOT endings before installation. That is a normal part of buying tires. You are checking stock age and matching tires across the axle.

What To Ask

• Can you show me the DOT ending on each tire before mounting?
• Are these four from the same production period?
• Is the spare close in age to the road tires?
• If one tire differs, why was it mixed into the set?

Those questions keep the chat grounded in facts. You are not guessing from tread shine or sidewall dressing. You are reading the build date straight from the tire.

Common Reading Mistakes

The biggest mistake is stopping at the first four digits you notice. Read the full DOT code from start to finish, then take the last four digits only. Another slip is checking one sidewall and assuming the code is missing. On many tires, the full TIN is printed on one side and a shorter version on the other.

A third mistake is treating the date code as the only thing that matters. Tire age sits beside tread wear, damage, inflation history, and the car maker’s fitment needs.

What To Do After You Read The Date

Write down the last four digits from each tire, then line them up by position: left front, right front, left rear, right rear, spare. That list tells you whether the car has a matched set, a mixed set, or one old outlier.

If the tires are older than you expected, or if one tire is much older than the rest, get a shop inspection before a long trip. The sidewall already tells the story. Once you know where the date sits, you can read it in seconds and make a sharper call.