Why 500 GB hard drive space less to 465.75 GB in your computer?

Answer 1

There are multiple legal ways of defining bytes, kilobytes, megabytes, gigabytes, terabytes, etc.

A standard kilobyte (KB) is defined as 1024 bytes. But drive manufacturers use the more 'lean' definition of kilobyte, which is a very strict 1000 bytes, as opposed to 1024 bytes.

After all, if you buy a 500Gb drive, and it actually had say 525Gb's on it, you'd be happy, not confused!

But no, they chose to go the opposite route, which, just my 'mere coincidence', happens to allow them to legally market undersized drives as judged by the standard definition of a KB.

IMO, it's all about the money, as it always is.

At this point in time, drives are essentially available in 500GB chunks. If you're uncertain as to whether one size will be enough, then you simply bump it up to the next notch and you're more than covered.

The other thing the article mentions is that formating a drive also reduces it's available storage space, so even if manufacturers used a 1024KB, you'd might still see a reduced available size because of the formating.

Answer 2

The '500GB' figure quoted by the manufacturer is the number of physical recordable bytes on the total disk surface. All disks have to be 'formatted' to work with the particular operating system on the computer (for most of us that means Windows). Formatting the disk involves writing various data structures on the disk so that the system can track and read the data that will be added later by the user. Data is written in blocks (called sectors) on the disk and there is a small control gap between the sectors. These various structures take up some of the space on the disk so it is no longer available to use. The '465GB' is what is left available for the system to use for 'useful' data - which will include things like directories and other things needed by Windows itself - the actual 'user' usable space will be smaller again. In total you can expect to 'lose' about 15% to 20% of the original physical capacity.