Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
Summary
Every tire carries its own date of manufacture, its size and its limits, moulded into the sidewall. The code that gives the age is the DOT Tire Identification Number, and the last four digits are the week and the year the tire was made. Federal regulation sets that format, so it reads the same way on every tire sold in the United States. This page shows you where to look and how to read what you find.
It does not tell you when to replace a tire, and it does not print a pressure. NHTSA says the correct inflation pressure is the one the vehicle manufacturer lists on the placard, not the maximum number moulded into the sidewall. Replacement age is a manufacturer question too, and vehicle makers and tire makers do not give the same answer. Both are marked here as consult-the-manufacturer on purpose.
Necessary equipment
| Item | Note |
|---|---|
| Flashlight optional | The light near a tire is often low. |
| Cloth | Use a cloth to remove dirt from the sidewall. |
| Pen and paper | Record the information for each tire. |
Specifications
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
Prepare the vehicle
Estimated under a minute
STOP THE VEHICLE AWAY FROM TRAFFIC BEFORE YOU START.
Traffic can kill you.
- Stop the vehicle on a level surface away from traffic.<1mReport a problem with step 1, Prepare the vehicle
- Set the parking brake.<1mReport a problem with step 2, Prepare the vehicle
- If the light is low, use a flashlight.<1mReport a problem with step 3, Prepare the vehicle
Find the tire identification number
Estimated 2 min
IF DIRT HIDES THE MARKINGS, CLEAN THE SIDEWALL WITH A CLOTH.
Do not use a sharp tool. A cut in the sidewall can cause damage to the tire.
- Look at the sidewall of the tire.<1mReport a problem with step 1, Find the tire identification number
- Find the letters DOT on the sidewall.<1mReport a problem with step 2, Find the tire identification number
- The letters DOT are a certification mark from the United States Department of Transportation.
- A new tire has 13 symbols after the letters DOT.
- A retreaded tire has 7 symbols after the letters DOT.
- If you do not find the letters DOT, look on the other side of the tire.<1mReport a problem with step 3, Find the tire identification number
- The regulation asks for the letters DOT on one sidewall only.
- Find the group of four numbers at the end of the tire identification number.<1mReport a problem with step 4, Find the tire identification number
- The regulation calls this group the date code.
Read the date code
Estimated 2 min
- Read the first two numbers of the date code.<1mReport a problem with step 1, Read the date code
- The first two numbers give the week of manufacture.<1mReport a problem with step 2, Read the date code
- A calendar week starts on a Sunday and ends on a Saturday.
- Read the last two numbers of the date code.<1mReport a problem with step 3, Read the date code
- The last two numbers give the last two digits of the year of manufacture.<1mReport a problem with step 4, Read the date code
- For example, the date code 0109 is week 01 of 2009.
- Do the same steps for each tire on the vehicle.<1mReport a problem with step 5, Read the date code
Read the other markings
Estimated 2 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Find the tire size on the sidewall.<1mReport a problem with step 1, Read the other markings
- Find the maximum inflation pressure on the sidewall.<1mReport a problem with step 2, Read the other markings
DO NOT USE THE PRESSURE ON THE SIDEWALL.
The sidewall shows the maximum pressure. The correct pressure is on the vehicle placard. A tire at the wrong pressure can fail and injure you.
- Do not use the maximum inflation pressure as the correct pressure.<1mReport a problem with step 3, Read the other markings
- Open the driver door.<1mReport a problem with step 4, Read the other markings
- Find the vehicle placard on the pillar or on the edge of the door.<1mReport a problem with step 5, Read the other markings
- Read the recommended cold inflation pressure from the vehicle placard.<1mReport a problem with step 6, Read the other markings
- The vehicle placard also gives the tire size for this vehicle.
Record the information
Estimated 2 min
Do not use one date code for all the tires.
Tires on one vehicle can have different dates.
- Record the week and the year of manufacture for each tire.1mReport a problem with step 1, Record the information
- Record the tire size for each tire.<1mReport a problem with step 2, Record the information
- Keep the record in the vehicle.<1mReport a problem with step 3, Record the information
Terminology
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
- tire identification number
- Also called: DOT number, DOT code, TIN, tire serial number, the four digit code on a tire
- date code
- Also called: born on date, tire age code, week and year code, last four digits
- sidewall
- Also called: side of the tire, tire wall, the writing on the tire
- vehicle placard
- Also called: tire and loading information label, door jamb sticker, door sticker, tire placard, B-pillar sticker
- maximum inflation pressure
- Also called: max psi, max pressure, the psi on the tire
- recommended cold inflation pressure
- Also called: correct tire pressure, recommended psi, door sticker pressure, proper tire pressure
- retreaded tire
- Also called: retread, recap, remould
When to use a professional
Stop if the sidewall has a cut. Stop if the sidewall has a bulge. Stop if the tire has a crack. Speak to a tire specialist.
A tire specialist must tell you when to replace a tire. This page does not give a replacement age. Vehicle manufacturers and tire manufacturers do not agree on an age. Read the documentation for your vehicle and your tires.
Common questions
How do I tell how old my tires are?
Look on the sidewall for the DOT Tire Identification Number and read the last four digits. The first two are the week of manufacture and the last two are the year. NHTSA gives the example 0308, which is a tire made in the third week of 2008. The number may be moulded on only one side of the tire, so look at both sides before you decide it is missing.
What does the 4 digit number on my tire mean?
It is the date code, the final group of the DOT Tire Identification Number. Federal regulation 49 CFR 574.5 requires four numerals: the week of the year, then the last two digits of the year. Week 01 is the first full calendar week of the year, and a calendar week runs from Sunday to Saturday.
What is the DOT number on a tire?
The letters DOT are a certification that the tire conforms to an applicable Federal Motor Vehicle Safety Standard. What follows is the Tire Identification Number: a plant code, then a manufacturer's code, then the date code. Under 49 CFR 574.5 a new tire carries 13 symbols and a retreaded tire carries seven.
Should I use the psi printed on my tire sidewall?
No. That number is the maximum permissible inflation pressure for the tire, not the right pressure for your vehicle. NHTSA is explicit that the correct pressure for your tire is what the vehicle manufacturer has listed, not what is listed on the tire itself. It is on the Tire and Loading Information placard, and 49 CFR 571.110 is what requires that placard to carry it.
How old is too old for a tire?
This page will not give you a number, because there is no single right one. NHTSA notes that some vehicle and tire manufacturers recommend replacing tires that are six to 10 years old regardless of treadwear, which is a range and an attribution rather than a rule. Your vehicle documentation and your tire maker are the authorities for your own tires. Read the date code first, so you know what you are asking them about.
Where is the tire and loading information sticker?
On the driver's side B-pillar in most vehicles. Where there is no B-pillar, or a placard there would not be legible, 49 CFR 571.110 allows the rear edge of the driver's side door or a position next to the driver's seat. NHTSA describes it as the label on the driver's side door edge, which is where most people find it.
Related procedures
- Read the treadwear, traction and temperature grades moulded on a tire and know what they do and do not compare
- How to check tire tread depth and know when you need new tires
- How to check the tire sealant and inflator kit your car carries instead of a spare tire
- How to check your tire pressure and put the right amount of air in your tires
- What the tire pressure light on my dashboard means and what to do about it
- How to check if your spare tire is there, in good shape and has enough air
- How to read the tire and loading information placard and work out how much load you have left for passengers and cargo
- Find the date code on a vehicle battery and work out how old it actually is
Sources
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
- Tier 1Tire Safety Ratings and Awareness (TireWise)
- Tier 149 CFR 574.5 — Tire identification requirements
- Tier 149 CFR 571.110 — FMVSS No. 110, Tire selection and rims
Revision history
Current version 1 · updated 2026-07-29 · next review due 2027-07-29
- v1 · 2026-07-29First draft. Built from 49 CFR 574.5, 49 CFR 571.110 and NHTSA TireWise. Every equipment-specific value publishes as consult-the-manufacturer.
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Comments and corrections
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.