Decode your tire's DOT code to find manufacturing date, current age, and replacement recommendation. Check if your tires are safe.
The Tire Age Calculator (DOT Code Decoder) is a safety diagnostic tool that evaluates 'rubber aging,' which is just as vital as physical tread wear. Tires undergo chemical aging where the rubber hardens and internal structures weaken over time, even if not driven. This tool converts complex DOT codes stamped on the sidewall into easy-to-understand manufacture dates and ages, warning of potential tire failure risks.
It extracts the last four digits of the DOT code, specifically the first two (week, 01-52) and the last two (year). By comparing this to the current date, the system calculates exactly how many years and months have passed since production. Following tire industry safety guidelines, it assigns a three-tier safety rating: under 6 years (Good), 6-10 years (Caution/Inspect), and over 10 years (Danger/Replace), providing engineering warnings about reduced grip and sidewall cracking risk.
Find the DOT code on the inner sidewall of your tire (the side facing the vehicle). Enter only the last 4 digits.
The first 2 digits are the week of manufacture (01–52) and the last 2 digits are the year. For example, "2419" means the 24th week of 2019.
Most tire manufacturers recommend replacing tires after 6–10 years regardless of tread depth. Tires 10+ years old should be replaced immediately.
The full DOT code begins with 'DOT' followed by a plant code, size code, and an optional manufacturer code, but only the final group encodes the date. Worked example: a code ending in 2823 means week 28 of 2023 (early July 2023); 0521 means week 5 of 2021. Since the year 2000, the date is always four digits (WWYY); tires made in the 1990s used three digits and are long past any safe service life.
A frequent mistake is reading the DOT code on the inboard sidewall, where many manufacturers stamp only a partial code and omit the date — the complete code with the four-digit date is required on at least one sidewall, usually the outboard side after mounting. Another error is judging a tire solely by tread depth: rubber oxidizes and hardens with calendar age regardless of mileage, so a deep-tread tire that is 12 years old can still fail.
Industry guidance from major makers and NHTSA recommends inspection of tires older than 6 years and replacement at or before 10 years from the manufacture date, irrespective of remaining tread. Many vehicle handbooks set the same 6-year inspection / 10-year replacement thresholds. Storage matters: heat, UV, and ozone accelerate aging, so a 'new' tire that sat in a warm warehouse for three years before sale has already consumed part of its chemical lifespan.