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See the attached. This is my main 120GB SSD in my desktop. You will see it was 119,000,000 bytes, which is where the manufacturer gets the size 120GB, but the OS only sees it as 110GB, due to binary addressing.
I'm still a bit confused on how this storage **** works. Sorry but can you please explain it again.
 
http://www.techzonez.com/forums/showthread.php/7243-Drive-Capacity-explained

Question
Why is my drive displaying a slightly less than expected capacity in Windows or Mac?

Answer
Determining drive capacity can be confusing at times because of the different measurement standards that are often used. When dealing with Windows and Mac based systems, you will commonly see both decimal measurements and binary measurements of a drive's capacity. In either case, a drive's capacity is measured by using the total number of bytes available on the drive. As long as the drive displays the correct number of bytes (approximate), you are getting the drive's full capacity.

Decimal vs. Binary:
For simplicity and consistency, hard drive manufacturers define a megabyte as 1,000,000 bytes and a gigabyte as 1,000,000,000 bytes. This is a decimal (base 10) measurement and is the industry standard. However, certain system BIOSs, FDISK and Windows define a megabyte as 1,048,576 bytes and a gigabyte as 1,073,741,824 bytes. Mac systems also use these values. These are binary (base 2) measurements.

Various Drive Sizes and their Binary and Decimal Capacities

Drive Size--------Approximate--------Decimal Capacity--------Approx Binary Capacity
in GB--------------Total Bytes------(bytes/1,000,000,000)-----(bytes/1,073,724,841)
10 GB-------------10,000,000,000------------10 GB------------------------9.31 GB
20 GB-------------20,000,000,000------------20 GB------------------------18.63 GB
30 GB-------------30,000,000,000------------30 GB------------------------27.94 GB
40 GB-------------40,000,000,000------------40 GB------------------------37.25 GB
60 GB-------------60,000,000,000------------60 GB------------------------55.88 GB
80 GB-------------80,000,000,000------------80 GB------------------------74.51 GB
100 GB-----------100,000,000,000-----------100 GB------------------------93.13 GB
120 GB-----------120,000,000,000-----------120 GB-----------------------111.76 GB
160 GB-----------160,000,000,000-----------160 GB-----------------------149.01 GB
180 GB-----------180,000,000,000-----------180 GB-----------------------167.64 GB
200 GB-----------200,000,000,000-----------200 GB-----------------------186.26 GB
250 GB-----------250,000,000,000-----------250 GB-----------------------232.83 GB
 
Okay, what hasn't been mentioned.

Capacity: 114GB
Available: Something less. (Capacity minus your stuff)

So if we are just doing byte math to calculate storage.

128GB -> 119GB

Does iOS not tally against Capacity?

On the iPhone 5s, the compressed update was 1.97GB

It's possible the OS, uncompressed is 5GB. But no one has said for certain that the OS usage is calculated against "Capacity" or the raw 119GB storage.

Additionally some space it taken, just for overhead, referring to file system. That takes space as well. I just don't recall. The more space you have IE: 128GB, 256GB etc, the more overhead there is, so the more that seems to be missing.

It's possible the answer to 114GB Capacity, is "ALL OF THE ABOVE" But we don't know for certain.
 
I am concerned reading this thread that there are a number of information which are misleading.

Let's consider the fact:
1) The OS overhead is a fixed space consumed across 16, 64 and 128GB

2) The larger the storage is, the higher overhead consumed for partition information (e.g. File Allocation Table, EXT2, HFS, etc)

3) Available sizes
a. 16GB - 9 GB available (after overhead and OS without additional software)
b. 64GB ??
c. 128GB - 114 GB available (after overhead and OS without additional software).

In the 3a and 3b, we can conclude that the OS overhead is not more than 7 GB at most (16GB with 9 GB available), so the only explanation why 128GB has 109/110GB available (18-19GB used, hence there is around 9-10GB difference of space used compared to 16GB) would be the additional overhead in partition and perhaps swap/virtual memory.

There were some comparison with SSD. This isn't relevant. There are two types of SSD, one with over-provisioning (128GB SSD advertised as 120GB, with 8GB for over provisioning i.e. spare to replace bad blocks), another SSD is without overprovisioning (128GB will be advertised as such). In either way, the formatted capacities will be less by a few gigs due to partition overhead. Over-provisioning is not applicable for iPhone.
 
I can't believe how much this gets asked given that it's not unique to iPhones. Hard drives, SSDs, and all storage devices are all marketed in gigabytes (GB) where 1 GB byte = 1,000,000,000 bytes. The virtual capacity reported by the OS is actually expressed in gibabytes (GiB) where 1Gib = 1,073,741,824 bytes.

That's the difference plus some for that used by formatting, OS, etc.

I am tired of seeing this response to this question. I understand how the conversion works. iTunes shows drive size and capacity in GB (same unit of measure), not GiB or gb (lower case ). In my case, what is blocking 13.66 GB (10.67%) of capacity? That seems high for partition / os overhead. Any ways, just tired of seeing the GB to GiB conversion reasoning when it doesn't apply to the intent of the question. See screen shot.
Screen Shot 2015-08-21 at 9.13.03 AM.png
 
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I am tired of seeing this response to this question. I understand how the conversion works. iTunes shows drive size and capacity in GB (same unit of measure), not GiB or gb (lower case ). In my case, what is blocking 13.66 GB (10.67%) of capacity? That seems high for partition / os overhead. Any ways, just tired of seeing the GB to GiB conversion reasoning when it doesn't apply to the intent of the question. See screen shot. View attachment 576492

It does apply, its the conversion and it needs to be accounted for. You have what appears to you as 14gb used but if that was actually the case then 16gb iPhones would only have 2gb of usable space available......?
 
I am tired of seeing this response to this question. I understand how the conversion works. iTunes shows drive size and capacity in GB (same unit of measure), not GiB or gb (lower case ). In my case, what is blocking 13.66 GB (10.67%) of capacity? That seems high for partition / os overhead. Any ways, just tired of seeing the GB to GiB conversion reasoning when it doesn't apply to the intent of the question. See screen shot. View attachment 576492

I am tired of people responding to 10 month old threads.
 
While I, in principle, agree, would you rather someone start more and more threads on the same topic that's already been discussed? Damned if you do; damned if you don't.

I completely understand if the user who bumped has a question that relates to the thread, but it is pointless if the bumping user is regurgitating information already present in the thread. Your response indicates you didn't notice that.
 
I completely understand if the user who bumped has a question that relates to the thread, but it is pointless if the bumping user is regurgitating information already present in the thread. Your response indicates you didn't notice that.

Now THAT, I will whole-heartedly agree with. Not much irks me more than members insisting that someone else just give them the answer, so they don't have to do the "work" of actually reading the thread. Or someone wants to throw in his/her .02 w/out reading and realizing nothing new is being contributed.
 
I am tired of seeing this response to this question. I understand how the conversion works. iTunes shows drive size and capacity in GB (same unit of measure), not GiB or gb (lower case ). In my case, what is blocking 13.66 GB (10.67%) of capacity? That seems high for partition / os overhead. Any ways, just tired of seeing the GB to GiB conversion reasoning when it doesn't apply to the intent of the question. See screen shot. View attachment 576492

iTunes is showing the drive size in GiB, with a GB unit of measure like all computers do. The iPhone's capacity is 119.2 GiB. With all the overhead for the OS, 114 GiB remaining makes sense.
 
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