Actual size of Extreme USB 3.0 32GB memory stick

Hi All

having checked the above 32GB flash drive, it lists 61282631 sectors of size 512bytes each.

This equates to a total size of 31.37670707 GB.

Surely this flash drive should be advertised as a 31GB drive not 32GB rounding to the nearest GB?

The size available for storage is listed as 61282599 which equates to 31.37669069 GB

Windows 7 reports a usable size of 31,361,351,680 bytes (29.2GiB)

I’m using 1GB = 1,000,000,000 bytes

Anybody else experience this anomoly?

The number represents the number of bits on the drive.  Formats; for Windows, Macs, Linux systems, have overhead; partition tables, cluster alignment requirements, etc and the resulting number of format used bits that you see will be less than the number of bits on the drive.  And different formats have different requirements so specifying a specific byte number would be inaccurate if the format changed.

I think one of the simpler way to explain this is. BIOS thinks it’s 32GB. You can check it. But Windows, this it’s 31.something. It’s just one of those calculation that are too stressful to understand. But it’s really 32GB.

It’s just one of those calculation that are too stressful to understand.

Really!!  I don’t find it that hard at all.

:smiley: Hi Dominator99,

Dear member of SanDisk Community, welcome.

Well, it’s very simple.

There are in all UFD, of any brand and capacity, a portion of the memory (~ 7%) not available to the user, which is used by the device’s internal software.

This, is notified, in very small print on the packaging.

In this memory portion, is the software that performs (among others) the following functions:

- Communication between the OS and the UFD.

- Simulation for that the OS, can detect the UFD, like it was a Disk.

- Booking of cells (~ 5%) , to replace those that they deteriorate, during ~ 10 years.  (Thus, it should never be defragment the UFD).

- Format.


Regards, Alfred.                                                                                     (Google translated)