SanDisk is a well-known name in the flash memory industry. Founded in 1988, they developed the first flash-based SSD. They were later acquired by Western Digital in 2016, before being spun off as a public company in early 2025.
SanDisk is a name I’ve long been aware of, and one that — prior to this project — I was biased in favor of. I have a number of single-board computers that take microSD cards, and I typically defaulted to the SanDisk Ultra 16GB for their storage — and most of the time, had no issues with them. And since they’re such a major brand, I wanted to make sure they were properly represented in this project.
This one was a donation from Richard Ahlquist — and in the interests of full disclosure, he mentioned that he had done some testing with it before sending it to me. I don’t know exactly what sort of testing he did with it or for how long — so it’s entirely possible that the results that I get from this one don’t reflect how a brand new card would perform.
As far as my criteria for determining name-brand cards goes, this card passes all the tests to be labelled as a name brand. (If SanDisk couldn’t pass my name-brand test, I’d need to go back and re-evaluate my criteria for determining what a name brand is…)
Performance on this card was…woof. This card immediately took the top spot for sequential read, sequential write, and random read speeds — and it’s very possible that the USB bus was the limiting factor here. (The reader was hooked up to a USB-C port rated for 10Gbps — although it only connected in 5Gbps mode.) Interestingly, however, random write scores were below average, coming in at just the 42nd percentile (as of the time of this writing). In fact, SanDisk as a whole has only been able to get average random write speeds — it’s something that they’ve consistently struggled with (with the exception of the two SanDisk Extreme 64GB’s that I got from AliExpress).
On the endurance front:
- Sample #1 has survived 8,576 read/write cycles in total so far and has not yet experienced any errors.
November 9, 2025 (current number of read/write cycles updates automatically every hour)