Tyre Code Decoder
Read a tyre's DOT code to find its manufacture week and year, and decode its load index and speed rating.
About this tool
Tyre Code Decoder
Read a tyre's DOT code to find its manufacture week and year, and decode its load index and speed rating.
Pick what you want to read, type the code from the sidewall and see what it means. This page brings together 2 separate tyre code decoder pages (DOT manufacture date, Load & speed rating) so you can compare them without hunting for the right one.
How to use Tyre Code Decoder
- 1
Open Tyre Code Decoder on AltFTool — it loads instantly in your browser.
- 2
Choose your code at the top: DOT manufacture date, Load & speed rating. On a phone it is a drop-down list.
- 3
Fill in the tyre code decoder for that code; each of the 2 options keeps its own rules, data and defaults.
- 4
Read the result, then switch code to compare. The page link keeps your code (?v=dot-date), so you can bookmark or share it.
Why use Tyre Code Decoder
All 2 in one place
DOT manufacture date, Load & speed rating and the rest sit behind one picker, so switching code takes a tap instead of a new search.
Built for each option
Every code keeps its own rules, numbers and defaults rather than one generic template.
Shareable view
The link remembers the code you picked, so a bookmark or a shared link opens straight on it.
Common use cases
- Checking how long a 'brand new' tyre has actually been sitting in the retailer's rack before you pay for it.
- Checking that a replacement tyre's load index is not lower than the one specified on the vehicle placard.
Frequently asked questions
Which code options does this tool cover?
2: DOT manufacture date, Load & speed rating. Pick one at the top of the tool; the page link updates (for example ?v=dot-date) so you can bookmark or share that exact view.
How do I read the DOT code on a tyre?
Find the DOT number on the sidewall and read the last group of digits. Four digits are week then year: 3624 means week 36 of 2024, roughly the first week of September that year. Three digits mean the tyre was made before 2000 and the code alone cannot tell you the decade. The full code appears on only one sidewall, so check both sides.
What does 91V mean on a tyre?
91 is the load index and V is the speed symbol: the tyre may carry 615 kg and is rated to 240 km/h. Four such tyres give 2,460 kg of total capacity. Both ratings apply only at the tyre's specified inflation pressure — an under-inflated tyre does not carry its rated load.