Problem about the capacity of sandisk extreme pro flash drive (512 GB)

USB Flash Drives All other USB Flash Drives
1

Hi there. I have recently bought a sandisk extreme pro solid state flash drive with 512 GB capacity. After formatting with both NTFS and exFAT, I noticed that the usable capacity is 460 GB. It seems something is wrong, because it should be approximately 476 GB. I searched all over the internet and did not find any satisfactory explanation.

Please consider before replying:

  1. I know the difference between GB and GiB. This is exactly why I mentioned that it should show 476. 460 is way too low and cannot be attributed to GiB conversion.

  2. I checked with diskpart and other tools and there are no additional/hidden partitions. Plus, I deleted the included software before formatting.

Thanks in advance!

2

Anyone?

3

Hi @saydash,

Please refer the article USB Drive, Memory Card & SSD Capacity in Operating System Does Not Match Label

Please contact the SD Technical Support team for best assistance and troubleshooting:https://kb.sandisk.com/app/ask

4

@Keerti_01: Did you read what I had written in the original post? I said that I already knew the difference between GB and GiB. Yet, you still refer this completely useless article to me.

I knew, I knew that there would be at least one stupid person like you who would reply to the post without fully reading it.

5

Having the exact same problem. The math does not add up and there seems to be no explanation anywhere.

6

Hi @Lezek,
You’re right — losing around 16 GB more than expected (476 GB expected vs 460 GB usable) is unusual and not fully explained by GB vs GiB conversion. In some cases, manufacturers reserve extra space for overprovisioning, firmware, or wear-leveling on flash-based drives to improve reliability and lifespan.

This reserved space is usually hidden from the user and not shown in tools like Disk Management or Diskpart. That could be why you’re seeing slightly lower usable capacity. If everything else on the drive works fine (no errors, good speed), then it’s normal and not a defect.