Unpowered SSD data retention time is quite long for SSDs that have not been used previously
The unpowered data retention time diminishes quickly with the number of times that the sectors used for storage have been written previously.
That is why the retention time of 1 year that is guaranteed for consumer SSDs is specified for a SSD that has been written with the maximum amount of data specified by the vendor.
Moreover, the retention time decreases quickly with increasing ambient temperature. It can be much longer in a fridge than in a place with tropical climate.
So that test proves nothing, because it has not been done in standard conditions. For a retention test, you must know how many TB of data have been written on the SSD before the test and which was the storage temperature.
If you have never written before the SSD and you store it in a cold place, it is likely that the retention time will be of many years instead of the guaranteed 1 year. Otherwise, it is reckless to hope for more than 1 year.
I found a similar (though much smaller! 1GB) Kingston drive from about 2008 that had been in storage since I moved overseas. 14 years later it still had all the data on it.
Unpowered SSD data retention time is quite long for SSDs that have not been used previously
The unpowered data retention time diminishes quickly with the number of times that the sectors used for storage have been written previously.
That is why the retention time of 1 year that is guaranteed for consumer SSDs is specified for a SSD that has been written with the maximum amount of data specified by the vendor.
Moreover, the retention time decreases quickly with increasing ambient temperature. It can be much longer in a fridge than in a place with tropical climate.
So that test proves nothing, because it has not been done in standard conditions. For a retention test, you must know how many TB of data have been written on the SSD before the test and which was the storage temperature.
If you have never written before the SSD and you store it in a cold place, it is likely that the retention time will be of many years instead of the guaranteed 1 year. Otherwise, it is reckless to hope for more than 1 year.
The standard conditions are worst-case. I think it's fair to also do common-case testing as long as the details are disclosed.
95 comments on "Flash media longevity testing – 6 years later" https://news.ycombinator.com/item?id=47298553 08-mar-2026
I found a similar (though much smaller! 1GB) Kingston drive from about 2008 that had been in storage since I moved overseas. 14 years later it still had all the data on it.
The older and the smaller are flash drives, the more likely it is to have longer retention times.
For low-density flash memories, it is possible to achieve up to 20 years of retention time.
This is no longer possible for high-capacity SSDs, which store multiple bits per cell in very small cells.