Fake USB & SD Check

Finds fake flash drives and memory cards that claim more space than they really have.

1Fill the drive with test data

Choose the USB drive or SD card (any folder on it). The test writes numbered files into a new folder, “TooLab-check”. Your own files aren’t touched.

How much to write

2Unplug, plug back in and verify

Safely remove the drive and plug it back in, so the computer forgets what it just wrote. Then choose the same drive. Every file is read back and checked.

Why fake drives exist

Cheap “1 TB” or “2 TB” flash drives and cards often hold only 8 to 64 GB. They tell the computer a bigger size, so files seem to save fine, but anything beyond the real size is lost or overwrites older files. Writing data and reading it back is the only way to know.

How long it takes

It depends on the drive’s speed. At 20 MB/s, writing 64 GB takes about 55 minutes and reading it back about 30. Choose 16 GB for a quicker first check.

Good to know

  • Keep the computer awake and don’t remove the drive during a step. The page asks the screen to stay on.
  • The test files are deleted after verifying. If a test was stopped, use the button below to delete them.
  • A drive that fails here is still dangerous with a smaller amount of data. Return it to the seller if you can.