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# Hermle Movement Date Codes

### How Old? Hermle Movement Date Codes
Dating a Hermle clock movement by decoding the
[date code](https://en.wikipedia.org/wiki/Calendar_date) stamp helps determine when the movement was made and whether it’s time for a replacement.
After locating the [Hermle movement](https://www.clockworks.com/clock-movement/hermle-clock-movement.html) date code, use the chart below to determine its age.
If the movement is **over 20 years old**, it’s time to replace it. Only movements **under 20 years old** should be considered for repair.
### Date Code System Change
Before 1987, Hermle movements were stamped with the year of production (e.g., “81” represents 1981).
Starting in 1988, letter codes replaced numbers—e.g., “A” for 1988, “B” for 1989, “C” for 1990, and so on.