The short answer
The last four digits of the DOT code are the date: the first two are the week (01 to 53) and the last two are the year, so 2223 means week 22 of 2023.
Tire makers show the week and year of manufacture in the date block of the DOT code: week 01 to 53, then the last two digits of the year (Continental explains the layout). The code is on one sidewall, sometimes only the inside one. This tool only decodes the date; it does not judge whether a tire is still safe. For guidance on tire age, follow the tire maker and your vehicle maker.
FAQ
Where is the DOT date code on a tire?
On the sidewall after the letters DOT, as the last four digits of the code. It can be on the inner sidewall only.
How do I read 2223?
The first two digits are the week and the last two are the year: week 22 of 2023.
Does the tool say when to replace a tire?
No. It only decodes the date and shows the age. Follow your tire maker’s and vehicle maker’s guidance.