f3 is a simple tool that tests flash cards capacity and performance to see if they live up to claimed specifications. It fills the device with pseudorandom data and then checks if it returns the same on reading.
Use these two programs in this order. f3write will write large files to your mounted disk and f3read will check if the flash disk contains exactly the written files:
f3probe is the fastest drive test and suitable for large disks because it only writes what’s necessary to test the drive. It operates directly on the (unmounted) block device and needs to be run as a privileged user:
f3fix creates a partition that fits the actual size of the fake drive. Use f3probe’s output to determine the parameters for f3fix:
f3write and f3read can be installed on Windows, but currently f3probe, f3fix, and f3brew require Linux. To use them on a Windows machine, use the Docker Installation. For f3write and f3read, read on.
f3write and f3read can be installed on Mac, but currently f3probe, f3fix, and f3brew require Linux. To use them on Mac, use the Docker Installation. For f3write and f3read, read on.