How much space after a Format

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How much space after a Format...If I buy a 1TB HDD, how much is left after a Format.
Also how much left after formating a 750GB HDD..(No good at maths)..
Trying to decide on 1x 1TB or 2x 750GB...
Cheers.
 
Well my my Maxtor OneTouch is 750GB and I had 698GB usable after the format, would have thought a 1TB drive would be around 959GB usable. I'm not totally sure what the percentage loss is though.
 
Well my my Maxtor OneTouch is 750GB and I had 698GB usable after the format, would have thought a 1TB drive would be around 959GB usable. I'm not totally sure what the percentage loss is though.

jak731 already stated how much would be usable m8 :p

I think you 'loose' around 6.8%, so expect around 932gb out of the 1tb drive.

The bigger the drive the more loss there is xD
 
Number of unformatted GB x 0.931322574... = formatted space

e.g 1TB = 1000GB (unformatted) = 931GB formatted
750GB = 698.5 formatted
etc etc


0.931322574... comes from:
1GB = 1,000,000,000 bytes unformatted
divide by 1024³ (to go back from bytes to GB including formatting)
 
to answer the OP's question,

1TB drive will give you 931GB of usable space
2x750GB will give you 1397 GB or 1.364TB (GB->TB divide by 1024 again)
 
MANY THANKS for the Info---It is Appreciated.
Have writen it all down so I won't forget..
 
Hard drives dont actually lose any space*, its just marketting spin. There are two "standard" names for data capacities. JEDEC recommend using Kilobyte as 1024 bytes, IEC on the other hand say that SI names (Kilo/Mega etc) are always 1000's.

As saying 1GB in 1000's increases the number thats just what the hard drive makers do.

SI/IEC actually think the computer industry should use KibiByte, MebiBytes. Personally I think it looks wrong on paper, and sounds ridiculous spoken. It's also rather ridiculous considering the underlying structure (the 8 bit byte) is a binary structure in the first place. It would have made just as much sence to say 1KB is 1000 x 10 bit words, it has just as much use for current binary computers (ie none at all), and of course it would have hurt the marketting of hard drives as 1000x 10 would have put 1KB at 10000 bits, while 1024x8 = 8192.

Perhaps its just a pet hate of mine, but im sticking with Kilo/Mega/Giga when talking about computer binary powers.

Hard drive makers picked up on this very early, 10meg drives were 10,000 byte capacity, but back then with MFM, and RLL formatting systems, I believe most hard drive makers did blame "formatting" on the space reduction.

* Ok a tiny amount of space is allocated to the boot sector, partition table, and the directory/file structures, but this is minor compared to the KB/KiB nonsense.
 
you 'loose' the same percentage regardless of the size of the drive so its irrelivant relly

hmmmmm,But as vertica said.....

e.g 1TB = 1000GB (unformatted) = 931GB formatted
750GB = 698.5 formatted
etc etc

-------------------------------------------
From 1tb 69gb is taken....

From 750 52gb is taken....
 
Just wanted to point out that some manufacturers use different size & number of platters therefore resulting in varying capacity when formatted, e.g. have 2 160GB HDs & capacity for one is 153.4GB, the other 149.1GB. They we're recently replaced with 2 500GBs from different manufacturers but capacity is the same on both i.e. 465.8GB.

vertica formula is accurate, but above is something to consider.
 
hmmmmm,But as vertica said.....

e.g 1TB = 1000GB (unformatted) = 931GB formatted
750GB = 698.5 formatted
etc etc

-------------------------------------------
From 1tb 69gb is taken....

From 750 52gb is taken....

yes, both ~93%

the only reason you 'lose' anythign is because of the those two different ways of measuring data. but, those ways of measuring data will be the same regardless of the difference in size and the percentage you 'loose' will also be the same.
 
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