Windows 7 - I can`t use all hard disk space

Well, i have an 500gb hdd but i can use only 465 gb ...why?

Manufacturers calculate drive capacity differently from how computers see storage space. Manufacturers use the decimal system, while computers use the binary system. So, when you convert from one system of measurement to another, there are discrepancies.

To calculate the actual drive capacity, divide the manufacturer's advertised capacity by 1.024 three times. For example, if you take an 80GB drive capacity and divide it by 1.024 three times, you will get 74.5GB of actual storage space. In your case, the real capacity would be about 465 gb (and so it is).

Answered a lot of times previously all over the internet. I dont have the time for explanation right now and so copied it from somewhere else.

500GB as it is on the package is 500,000,000,000 Bytes. Since a kilobyte is 1024 bytes and a megabyte is 1024 kilobytes and a gigabyte is 1024 megabytes, the calculation doesn't come out as 500 GBs of space. It's basically a marketing scheme to make you think you're getting more space than you are, all hard drives are sold that way. It's 500 billion bytes and not 500 GBs, even though that's what it says. 465 GBs of space is all there really is. If you divide 500,000,000,000 by 1024, then by 1024, then by 1024 again, you get the actual space your computer will use, which comes out to 465.66 GB.



In simple words manufacturers says 1KB for 1000 bytes whereas it is actually 1024 bytes ... so you are missing 24 bytes for a KB. It goes on in the same for the rest and it is there is where you lose it.

Take a look here:

Hard Drive Size Capacities Calculator

Exactly what Bill2, and others, said and to make you happy when all is said and done you have the equivalent of 500Gb when filled.

Nice find! Bookmarked!

@pedala - not mentioned but also a factor is that some disk space is consumed by the file and partition tables. When you partition (even if only one partition, which all drives must have at least one) and format a drive, all the storage locations are mapped and stored in tables so the drive can find them. Think of a 500 page reference book where several pages are consumed by the Table of Contents and the index pages.

Thanks for your help. I understand

Realize you got your answer but we have had an older sticky of this subject here if you want to check it out: HDD's - the Advertized size vs the Actual size.