DOT tire identification number (DOT EJ7 LN4R 2319)
DOT is the maker’s certification that the tyre meets the US Federal Motor Vehicle Safety Standards; the tire identification number after it names the factory (plant code), the tyre (manufacturer’s code) and the week and year it was made.
What to do with it
Keep the full number if you register the tyre or look up a recall: it traces the tyre to its factory, its type and its production week — 49 CFR part 574 is the US tire identification and recordkeeping rule. The plant code tells you which factory; the last four digits give the date — the date decoder reads them.
Read the four digits on your tyre: the tyre date decoder →
- What it looks like
- The letters DOT followed by groups of letters and digits, 13 symbols in all on a new tyre: DOT, a 3-symbol plant code, a 6-symbol manufacturer’s code, then the 4-digit date.
- Set by
- 49 CFR 574.5, § 574.5(a)(1), (b)(1)–(3), (c), (e)(1); 49 CFR 571.139, S5.5(a) and S5.5.1
In detail
- Plant code: the first group, three symbols, assigned by NHTSA to the manufacturer or retreader. Older tyres may carry a two-symbol code; the regulation allowed those until 13 April 2025.
- Manufacturer’s code: six symbols the maker chooses to identify the tyre’s size, characteristics or brand owner; the maker keeps the record of what each code means.
- Date code: four digits, week then year — see its own page.
- Retreaded tyres carry a shorter, seven-symbol TIN and a letter R, which is not part of the TIN.
- In the US the full TIN must be on the intended outboard sidewall (since 1 September 2009); the other side may show it without the date.
What it does not mean
DOT is not an approval stamp issued by a government office: the regulation calls it a certification by the manufacturer. It says nothing about the tyre’s grip, wear or age.
Markings that go with it
Sources
Each document was fetched and read on the date shown; the clause is the one that sets this marking.
- US National Highway Traffic Safety Administration, on eCFR: 49 CFR 574.5 — Tire identification requirements — § 574.5(a)(1), (b)(1)–(3), (c), (e)(1): New tyres carry “a TIN consisting of 13 symbols”; the plant code “consisting of three symbols, must be the first group”; “The DOT symbol constitutes a certification that the marked tire conforms to an applicable Federal Motor Vehicle Safety Standard.” Checked 2026-09-28.
- US National Highway Traffic Safety Administration, on eCFR: 49 CFR 571.139 — Standard No. 139, New pneumatic radial tires for light vehicles — S5.5(a) and S5.5.1: Each tyre must carry “The symbol DOT” and the TIN on the intended outboard sidewall. Checked 2026-09-28.