
<ref name=thor2000>{{Cite journal |title=Prefixes for binary multiples |author=A.J.Thor |journal=Metrologia |year=2000 |volume=37 |issue=81 |url=http://ej.iop.org/links/rDo33k,Nb/lrUHtuYE3BGiff6cav5vpA/me0112.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://ej.iop.org/links/rDo33k,Nb/lrUHtuYE3BGiff6cav5vpA/me0112.pdf |archive-date=2022-10-09 |url-status=live |doi=10.1088/0026-1394/37/1/12 |page=81 |bibcode=2000Metro..37...81T |s2cid=250774728 }}{{dead link|date=July 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

<ref name=IBMc2003>{{cite web|url=http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2075.html |title=System/360 Model 75 |publisher=[[IBM]]|access-date=2015-03-10|work=IBM Archives|date=23 January 2003 |quote=up to 1,048,576 characters of information}}</ref>

<ref name=iecpref>The term '''IEC binary prefix''' or '''IEC prefix''' refers to the prefixes such as kibi, mebi, gibi, etc., or their corresponding symbols Ki, Mi, Gi, etc., first adopted by the [[International Electrotechnical Commission]] (IEC). Such prefixes are commonly used with the units bits or bytes (or less commonly, compound units derived from them such as bytes/second) and always denote powers of 1024; that is, they are always used as binary prefixes. Thus 1 mebibyte of RAM is 1024<sup>2</sup> bytes of RAM, one gibibyte or 1&nbsp;GiB of RAM is 1024<sup>3</sup> bytes, and so on.</ref>


 {{As of|February 2010}}, most software did not distinguish symbols for binary and decimal prefixes.<ref group="defn." name=decpref>A '''decimal prefix''' is a prefix that denotes a [[Exponentiation|power]] of 1000. For example, "kilo" denotes 1000, "mega" denotes 1000<sup>2</sup> or one million, "giga" denotes 1000<sup>3</sup> or one billion, and so on. SI prefixes are decimal prefixes.</ref> The [[International Electrotechnical Commission|IEC]] binary naming convention is used by some to make this distinction.

One of the stated goals of the introduction of the IEC prefixes was "to preserve the SI prefixes as unambiguous decimal multipliers".<ref name=IEEE2003/> Programs such as [[fdisk]]/[[cfdisk]], [[parted]], and [[apt-get]] use SI prefixes with their decimal meaning.

<gallery perrow="6">
Image:Bittornado screenshot showing use of IEC and SI prefixes.png|BitTornado uses standard SI prefixes for data rates and IEC prefixes for file sizes
Image:Deluge_using_Si_prefix_for_wiki_CD.png|[[Deluge (BitTorrent client)]] uses IEC prefixes for data rates as well as file sizes
</gallery>

Example of the use of IEC binary prefixes in the [[Linux]] operating system displaying traffic volume on a network interface in kibibytes (KiB) and mebibytes (MiB), as obtained with the [[ifconfig]] utility:
<pre>
eth0      Link encap:Ethernet [...]
          RX packets:254804 errors:0 dropped:0 overruns:0 frame:0
          TX packets:756 errors:0 dropped:0 overruns:0 carrier:0
          [...]
          RX bytes:18613795 (17.7&nbsp;MiB)  TX bytes:45708 (44.6&nbsp;KiB)
</pre>

Software that uses IEC binary prefixes for powers of 1024 ''and'' uses standard SI prefixes for powers of 1000 includes:

{{div col|colwidth=22em}}
* [[GNU Core Utilities]]<ref name=gnu2002>{{cite web
|url=https://www.gnu.org/software/coreutils/manual/html_node/Block-size.html#Block-size
|title=2.2 Block size
|access-date=2007-05-20
|date=2002-12-28
|work=[[GNU Core Utilities]] manual
|publisher=[[Free Software Foundation]]
}}</ref>
* [[GParted]]<ref name=gnu2006>{{cite web
|url=http://sourceforge.net/project/shownotes.php?release_id=389304&group_id=115843
|archive-url=https://web.archive.org/web/20070116033636/http://sourceforge.net/project/shownotes.php?release_id=389304&group_id=115843 |archive-date=2007-01-16
|title=gparted-0.2 changelog
|access-date=2007-05-20
|date=2006-01-30
|work=[[SourceForge]]
}}</ref>
* [[FreeDOS#FreeDOS-32|FreeDOS-32]]<ref name=fdos2009>[http://freedos-32.sourceforge.net/showdoc.php?page=standards FreeDOS-32 – Standards Compliance] {{webarchive |url=https://web.archive.org/web/20090112230144/http://freedos-32.sourceforge.net/showdoc.php?page=standards |date=12 January 2009 }}</ref>
* [[ifconfig]]<ref name=linux2005>{{cite web
 |url=http://www.annodex.net/cgi-bin/man/man2html?8+ifconfig
 |title=IFCONFIG
 |access-date=2007-05-20
 |date=2005-06-30
 |work=[[Manual page (Unix)|Linux Programmer's Manual]]
 |quote=Since net-tools 1.60-4 ifconfig is printing byte counters and human readable counters with IEC 60027-2 units. So 1&nbsp;KiB are 2^10 byte.
 |archive-url=https://web.archive.org/web/20070216045538/http://www.annodex.net/cgi-bin/man/man2html?8+ifconfig
 |archive-date=16 February 2007
 }}</ref>
* [[GNOME]] Network<ref name=gnome2013>{{cite web|url=https://projects.gnome.org/gnome-network/index.shtml |title=GNOME Network |publisher=Gnome.org |access-date=2012-01-26 |url-status=live |archive-url=https://web.archive.org/web/20130121122842/http://projects.gnome.org/gnome-network/index.shtml |archive-date=21 January 2013 }}</ref>
* [[SLIB]]<ref name=jaff2012>{{cite web |url=http://swissnet.ai.mit.edu/~jaffer/SLIB.html |title=SLIB |publisher=Swissnet.ai.mit.edu |date=2010-06-30 |access-date=2012-01-26 |archive-url=https://web.archive.org/web/20080807042947/http://swissnet.ai.mit.edu/~jaffer/SLIB.html |archive-date=2008-08-07 }}</ref>
* [[Cygwin/X]]<ref name=cygwin2001>{{cite web|url=http://cygwin.com/xfree/ |archive-url=https://web.archive.org/web/20011110203935/http://cygwin.com/xfree/ |archive-date=2001-11-10 |title=Cygwin/XFree86 |date=2001-11-10 |access-date=2012-01-26}}</ref>
* [[HTTrack]]<ref name=httxxxx>{{cite web|url=http://forum.httrack.com/readmsg/3011/3006/index.html |title=Re: minor typo – HTTrack Website Copier Forum |publisher=Forum.httrack.com |access-date=2012-01-26}}</ref>
* [[Pidgin (IM client)]]<ref name=pidgxxxx>{{cite web|url=http://developer.pidgin.im/ticket/1684 |title=Developer discussion |publisher=Developer.pidgin.im |access-date=2012-01-26}}</ref>
* [[Deluge (software)|Deluge]]<ref name=delu2013>{{cite web
|url=http://dev.deluge-torrent.org/changeset/527
|archive-url=https://archive.today/20130414141307/http://dev.deluge-torrent.org/changeset/527
|archive-date=2013-04-14
|title=Deluge changeset
|access-date=2007-06-13
|quote=proper prefix for size
}}</ref>
* [[yafc]]<ref name=yafcxxxx>{{cite web|url=http://sourceforge.net/project/shownotes.php?release_id=240228&group_id=11340 |title=Files |publisher=SourceForge.net |access-date=2012-01-26}}</ref>
* [[tnftp]]<ref name=tnftp2009>[http://archive.netbsd.se/?ml=pkgsrc-changes&m=4873558 archive.netbsd.se] {{webarchive |url=https://web.archive.org/web/20090826161925/http://archive.netbsd.se/?ml=pkgsrc-changes&m=4873558 |date=26 August 2009 }}</ref>
* [[WinSCP]]<ref name=winscpxxx>{{cite web|url=http://winscp.net/eng/docs/history |title=Recent Version History |publisher=WinSCP |access-date=2012-01-26}}</ref>
* [[MediaInfo]]<ref name=minfxxxx>{{cite web
| title = MediaInfo
| publisher = MediaInfo main site
| url = http://mediainfo.sourceforge.net/
| access-date = 2010-03-01
}}</ref>
{{div col end}}

Software that uses standard SI prefixes for powers of 1000, and does not use any prefixes for powers of 1024, includes:
* Mac OS X v10.6 and later for hard drive and file sizes<ref>{{cite web
|url=http://www.macprime.ch/news/article/snow-leopard-1-gb-1000-mb/
|title=News – Snow Leopard: 1&nbsp;GB = 1000&nbsp;MB
|publisher=macprime.ch
|date=2009-06-19
|access-date=2009-08-29
|archive-url=https://web.archive.org/web/20090925073648/http://www.macprime.ch/news/article/snow-leopard-1-gb-1000-mb
|archive-date=25 September 2009
}}</ref><ref>{{cite web
| url = http://support.apple.com/kb/TS2419
| title = How Mac OS X reports drive capacity
| publisher = Apple
| date = 2009-08-27
| access-date = 2009-08-30}}</ref>

Software that supports decimal prefixes for powers of 1000 ''and'' binary prefixes for powers of 1024 (but does not follow SI or IEC nomenclature for this) includes:
* [[4DOS]] (uses lowercase letters as decimal and uppercase letters as binary prefixes)<ref name="4DOS_4.00_HELP">{{citation |title=4DOS.DOC 4.00 |title-link=4DOS 4.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-first3=Rex C. |author-last3=Conn |date=1991-11-01 |version=4.00}}</ref><ref name="4DOS_8.00_HELP">{{cite book |title=4DOS 8.00 online help |title-link=4DOS 8.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-link2=Tom Rawson |author-first3=Rex C. |author-last3=Conn |author-link3=Rex C. Conn |author-first4=Matthias R. |author-last4=Paul |author-first5=Charles E. |author-last5=Dye |author-first6=Luchezar I. |author-last6=Georgiev |date=2002-02-27}}</ref>