CapacityTester - Detect Fake USB Flash Drives
Many USB flash drives on the market are fakes. Especially the cheap ones that are shipped directly from Asia.
A fake memory stick or card claims to have a higher capacity than it really has. For example, a fake drive would pretend to have a capacity of 128 GB, but in reality, it only has a 4 GB chip. Data written beyond this 4 GB limit will be lost. In some cases, the data written beyond that limit is simply lost without a warning. In other cases, writing beyond the limit will brick the drive. Either way, data will be lost if this goes undetected.
How does the test work?
This simple tool attempts to determine if a drive is a fake or not.
All it does is fill the volume with test data and verify if the data on the volume is correct. This would fail on a fake and an error message will give you the approximate position of the error, which may be an indication of the drive's real capacity.
If the test succeeds, the drive is good and you can use it without having to worry about your data.
If you have a genuine flash drive that has become defective, the test will also fail. In other words, a failed test does not necessarily mean that you have a fake drive, but it does mean that there is something wrong with it which causes data loss. The program does not detect and report the type of fake, it just reports an error and where the error has occurred. This should provide a rough estimate on the real capacity of the drive, but no guarantees are made regarding the accuracy of the result.
How do I use CapacityTester?
Just mount your USB drive, for example by opening it in your favorite file manager. Make sure it's completely empty. The volume must be completely empty for the test to provide reliable results. Again, empty.
Open CapacityTester, select your USB flash drive and start the test. Lean back and grab a cup of tea, this will take a while.
Which platforms are supported?
Linux and Windows.
Pre-compiled binaries are attached to this release.
Does this have a command-line interface?
Yes! This program does have a command line interface too. Use the -platform offscreen switch.
Bugs
This is new software, it might have bugs. If you've found one, please open an issue.
Binaries
Two pre-compiled binary packages are attached to this release.
The Debian 7 binary should also run on many other Linux distributions like Fedora or Ubuntu. The Qt 5 runtime libraries must be installed (or provided manually, see README under "Call").
The Windows 7 64-bit package runs on Windows 7 or higher. This zip archive contains a standalone exe file that can be used right away (It contains runtime library files and the dynamically linked program file). Just download and run it, no installation required.