Whenever I get a new SD card or USB stick, or any kind of storage, I want to test it out to make sure it’s “legit.”
Sometimes, on Amazon and other online stores, they sell knock-off and counterfeit SD cards that don’t really have the advertised capacity or speed.
So before I use them in my drones or cameras, I run them through f3, which fills up the SD card with random data, and verifies the write speed.
you can grab f3 here: https://github.com/AltraMayor/f3
Here’s an example:
After running f3write, it’s a good idea to run f3read of course, which will you if the writing was successful, and if there are any bad sectors on the media.