# Why does my 6G iPod mini only hold 5.6G? **URL:** \ **Category:** Factual Questions\ **Created:** [May 1, 2005, 11:56am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949 "2005-05-01T11:56:20Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 1, 2005, 11:56am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/1 "2005-05-01T11:56:20Z")
Is this marketing by rounding? iTunes library has 5.75G worth of material but it tells me my iPod mini 6G won’t hold that much. It creates a new folder that it can load the iPod from and it appears that it maxes out at 5.6G. Nowhere on Apple’s site does it give the capacity as anything other than 6G. I understand rounding but maybe I should have rounded my payment down to the nearest hundred. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 1, 2005, 11:58am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/2 "2005-05-01T11:58:33Z")
Sorry, I guess there should be a question in there. Am I doing something wrong or is the capacity truly 5.6G? ---
**Author:** ![thoth200](https://avatars.discourse-cdn.com/v4/letter/t/eb8c5e/32.png) [@thoth200](https://boards.straightdope.com/u/thoth200)\ **Post date:** [May 1, 2005, 12:08pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/3 "2005-05-01T12:08:47Z")
> [@CookingWithGas](#): > > Sorry, I guess there should be a question in there. > > Am I doing something wrong or is the capacity truly 5.6G? I may be wrong but I think your missing 400 MB of space is the file allocation table. the space where the information of where each file is located on the drive so it can find it when you need it ---
**Author:** ![ParentalAdvisory](https://avatars.discourse-cdn.com/v4/letter/p/53a042/32.png) [@ParentalAdvisory](https://boards.straightdope.com/u/ParentalAdvisory)\ **Post date:** [May 1, 2005, 12:12pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/4 "2005-05-01T12:12:34Z")
Probably something to do with binary and decimal differences. Check out this site and look at the table on the bottom of the page. It’s Western Digital’s site, but the idea is basically the same for all harddrives: > [@](#): > > 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. [http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduser/std\_adp.php?p\_faqid=615&p\_created=1034613413&p\_sid=qzEY8kEh&p\_lva=&p\_sp=cF9zcmNoPSZwX3NvcnRfYnk9JnBfZ3JpZHNvcnQ9JnBfcm93X2NudD03NjcmcF9wcm9kcz0mcF9jYXRzPSZwX3B2PSZwX2N2PSZwX3BhZ2U9MQ\*\*&p\_li=&p\_topview=1](http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduser/std_adp.php?p_faqid=615&p_created=1034613413&p_sid=qzEY8kEh&p_lva=&p_sp=cF9zcmNoPSZwX3NvcnRfYnk9JnBfZ3JpZHNvcnQ9JnBfcm93X2NudD03NjcmcF9wcm9kcz0mcF9jYXRzPSZwX3B2PSZwX2N2PSZwX3BhZ2U9MQ**&p_li=&p_topview=1) ---
**Author:** ![Revtim](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/revtim/32/1042_2.png) [@Revtim](https://boards.straightdope.com/u/Revtim)\ **Post date:** [May 1, 2005, 12:13pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/5 "2005-05-01T12:13:55Z")
I suppose it’s like PC hard drives, where some percentage of the drive must be used for formatting and indexing purposes. ---
**Author:** ![Anachronism](https://avatars.discourse-cdn.com/v4/letter/a/e56c9b/32.png) [@Anachronism](https://boards.straightdope.com/u/Anachronism)\ **Post date:** [May 1, 2005, 1:00pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/6 "2005-05-01T13:00:41Z")
I belive part of it is due to binary and decimal differences like **Parental Advisory** said, but the iPod also must have some sort of operating system that takes up some room. ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [May 1, 2005, 1:20pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/7 "2005-05-01T13:20:01Z")
Seems like **Parental Advisory** may have one aspect of it. On the bottom of the [iPod page](http://www.apple.com/ipod/specs.html), it says: > [@](#): > > 1GB = 1 billion bytes; actual formatted capacity less. > Capacity based on 4 minutes per song and 128-Kbps AAC encoding. If you take 6 GB in base 10, you get 5.59 GB in base 2 (6 billion / 1024 / 1024 / 1024). Hmm… strangely, if my math is correct, that means your hard drive hasn’t even lost any space due to formatting (even though it should, as Apple points out). Or maybe iTunes just displays the formatted capacity in base 10, in which case **thoth200** would be right. On the other hand, Apple rates the mini as capable of holding 1500 songs. By their definition, that would be approximately 5.49 GB of useable space, so it’s in line with what you’re getting right now. (1500 songs \* 128 kbps \* 60 secs in a min \* 4 min / 8 to get bytes / 1024 / 1024 = 5.49 GB in base 2). Heh. I guess whichever way you look at it, you’re stuck with about 5 and a half gigs of space. And **Anachronism** : Are you sure the OS is stored on the hard drive and not in ROM or similar? ---
**Author:** ![ParentalAdvisory](https://avatars.discourse-cdn.com/v4/letter/p/53a042/32.png) [@ParentalAdvisory](https://boards.straightdope.com/u/ParentalAdvisory)\ **Post date:** [May 1, 2005, 1:47pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/8 "2005-05-01T13:47:35Z")
> [@Reply](#): > > And **Anachronism** : Are you sure the OS is stored on the hard drive and not in ROM or similar? I’m not too familiar with the iPods, but an OS that is as simple as managing MP3’s and simple menus for a harddrive shouldn’t be too large at all. Me thinks the OS is located on an on-board chip. If that’s the case, it would make harddrive swaps much easier in case of failure, or upgrades. An iPod guru would confirm this though, so take it for what it’s worth. ---
**Author:** ![postcards](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@postcards](https://boards.straightdope.com/u/postcards)\ **Post date:** [May 1, 2005, 4:11pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/9 "2005-05-01T16:11:21Z")
I think flash memory needs to use some space on the card for FAT’s. The 512MB cards I use in my digital camera only show 488MB after formatting. ---
**Author:** ![Anachronism](https://avatars.discourse-cdn.com/v4/letter/a/e56c9b/32.png) [@Anachronism](https://boards.straightdope.com/u/Anachronism)\ **Post date:** [May 1, 2005, 6:25pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/10 "2005-05-01T18:25:59Z")
> [@Reply](#): > > And **Anachronism** : Are you sure the OS is stored on the hard drive and not in ROM or similar? No, looks like I was wrong :o > **[Why doesn’t my iPod show the full Hard Drive capacity that I paid for?!](https://www.ilounge.com/index.php/faqs/answers/why-doesnt-my-ipod-show-the-full-hard-drive-capacity-that-i-paid-for/)** > > Contrary to popular belief, this anomaly is not caused by factory-installed programs, file system overhead, or swap space… it’s about math and ... ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 1, 2005, 7:57pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/11 "2005-05-01T19:57:33Z")
Thanks. Regardless of the math, here are the facts: Specs say it has a 6G capacity iTunes says it has 5.6G of content but won’t take any more So I guess it is what it is, but I don’t like surprises. ---
**Author:** ![Cardinal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cardinal/32/4000_2.png) [@Cardinal](https://boards.straightdope.com/u/Cardinal)\ **Post date:** [May 1, 2005, 9:27pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/12 "2005-05-01T21:27:42Z")
> [@Anachronism](#): > > No, looks like I was wrong :o > > [http://www.ipodlounge.com/index.php/faqs/answers/why-doesnt-my-ipod-show-the-full-hard-drive-capacity-that-i-paid-for/](http://www.ipodlounge.com/index.php/faqs/answers/why-doesnt-my-ipod-show-the-full-hard-drive-capacity-that-i-paid-for/) Exactly. I just bought a 200GB drive, and was upset that Windows wanted to “lose” 14GB. That 14 GB instead corresponds to the 7% loss when converting from “marketing” GB to real, usable GB. Take any box cover GB and subtract 7% to get what your real storage capacity will be. ---
**Author:** ![Cleophus](https://avatars.discourse-cdn.com/v4/letter/c/a88e57/32.png) [@Cleophus](https://boards.straightdope.com/u/Cleophus)\ **Post date:** [May 2, 2005, 2:07am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/13 "2005-05-02T02:07:38Z")
It’s not a matter of lost space, simply different units of measurement. Just as you wouldn’t say a piece of rope advertised as 3 yards long has lost length if you measure it in the metric system and find it is 2.7432 meters long, it is also incorrect to say a hard drive measured in binary bytes has lost space when compared to the equivalent measurement in decimal bytes. ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [May 2, 2005, 9:10am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/14 "2005-05-02T09:10:28Z")
> [@Cleophus](#): > > It’s not a matter of lost space, simply different units of measurement. Just as you wouldn’t say a piece of rope advertised as 3 yards long has lost length if you measure it in the metric system and find it is 2.7432 meters long, it is also incorrect to say a hard drive measured in binary bytes has lost space when compared to the equivalent measurement in decimal bytes. > [@](#): > > It’s not a matter of lost space, simply different units of measurement. Yeah, but it’s still confusing. With metric/imperial, it’s easy to tell which system you’re using because it’s followed by “in” or “cm” (unless you’re NASA). This is something different because the unit of measurement doesn’t change, the number base system does. Most people aren’t used to working with anything other than base 10, and to make matters worse, the manufacturers themselves only specify the base in small print (if at all). There’s no easy way to tell how much space “60GB” actually refers to. It’s more like somebody selling you 10 yards of rope, only to tell you later than the 10 was in base 2. Then you find yourself stuck with 2 actual yards of rope. They’ve been trying to differentiate the two systems by using things like “Gigabyte” and “Gibibyte” (GB and GiB), but nobody listens. ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [May 2, 2005, 9:18am UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/15 "2005-05-02T09:18:05Z")
Just to correct myself: Maybe it’s not that nobody listens, but the problem is you can’t tell apart the new “GB” (base-10) from the old “GB” that people still use as base-2. “GiB” is okay but “GB” is still ambiguous. ---
**Author:** ![butler1850](https://avatars.discourse-cdn.com/v4/letter/b/779978/32.png) [@butler1850](https://boards.straightdope.com/u/butler1850)\ **Post date:** [May 2, 2005, 3:21pm UTC](https://boards.straightdope.com/t/why-does-my-6g-ipod-mini-only-hold-5-6g/301949/16 "2005-05-02T15:21:17Z")
Welcome to the wonderful world of computing. It’s driven us in the industry nuts for years. Get used to it, whenever the marketing people \ can figure out a way to make something look bigger, when it’s really the same, they’ll jump on it! \