GrailHow to Read Hot Wheels Base Codes: Find the Year Your Car Was Made
Updated October 2026 · Evergreen guide
Flip a Hot Wheels car over and you'll usually see two dates. One is misleading and one is exactly what you're looking for.
The copyright year is not the production date
A line like "©2008 Mattel" is the copyright date of the casting (the car's design). It's often the year before the casting first came out, and it usually stays the same for the casting's whole life, so a car made last year can show a decades-old date.
The base code: letter plus week
Since 2008, Mattel has stamped a base code such as M36 on the base. The letter is the year it was made, and the two digits are the week of that year. M36 means the 36th week of 2019 (early September).
| Letter | Year | Letter | Year |
|---|---|---|---|
| A | 2008 | K | 2017 |
| B | 2009 | L | 2018 |
| C | 2010 | M | 2019 |
| D | 2011 | N | 2020 |
| E | 2012 | P | 2021 |
| F | 2013 | R | 2022 |
| G | 2014 | S | 2023 |
| H | 2015 | T | 2024 |
| J | 2016 | U | 2025 |
| V | 2026 |
The letters I, O and Q are skipped.
Extra letters and other formats
- Since about 2018, some codes have a third letter (e.g. U02A). Sources disagree on what it means; one reference links it to the factory, so treat that as unconfirmed.
- Some cars use a four-digit code instead, where the first three digits are the day of the year and the last digit is the year. For example, 1987 means the 198th day of 2017, though the single year digit can be ambiguous.
- A base code can be newer than a car's model year, because popular releases are sometimes produced again later.
Why it matters
Base codes help you date loose cars, spot later production runs, and check whether a car matches the release a seller claims.
Sources: Hot Wheels Wiki: Base codes, Wheel Wonderland base code study, Hot Wheels (WikiMili/Wikipedia).