Uniform Type Identifiers

Uniform Type Identifiers were introduced by Apple in Mac OS 10.4 (Tiger) as a modern replacement to traditional means for identifying the type of data contained within byte streams such as disk files and the clipboard.

On the Macintosh, 4-character codes known as file types have been used traditionally for this purpose, while filename extensions were (and are still) used on platforms such as Windows and Unix. In adittion to file types and filename extensions, the Internet has introduced mime types for identifying streams of data delivered through the network.

Example: here are some traditional ways for identifying a JPEG image:

In the UTI universe, all these are replaced by a single string: "public.jpeg".

UTIs are plain strings, commonly formed in reverse-DNS notation:

UTIs also provide a mechanism for the classification of data types. For example, the "public.jpeg" UTI conforms to the "public.image" UTI. This mechanism can be used by applications on Mac OS X for specifying classes of accepted data types in cases such as the file selection dialogs, the pasteboard, and drag-and-drop.

The QDrop plug-in area fully supports this classification mechanism. For example, suppose that a QDrop plug-in area has to be configured to accept drops of image files. Instead of specifying a list of all image UTIs ("public.jpeg", "public.tiff", and so on), the "public.image" UTI can be used and the plug-in area will accept any data type that conforms to the "public.image" UTI.

The tables below contain the majority of UTIs defined by Mac OS X. Note that this list is not exhaustive; third party applications may define UTIs for their own private use and data formats. For example, 4D defines "com.4d.private.text.native" and a few others for use with its pasteboard related commands.

Abstract base types
UTIDescriptionConforms to
public.item generic base type for most things (files, directories)
public.content base type for anything containing user-viewable document content (documents, pasteboard data, and document packages)
public.composite-content base type for content formats supporting mixed embedded content (i.e., compound documents) public.content
com.apple.application base type for Mac OS X applications, launchable items
public.message base type for messages (email, IM, etc.)
public.contact contact information, e.g. for a person, group, organization
public.archive an archive of files and directories
public.disk-image a data item mountable as a volume public.archive
Concrete base types
UTIDescriptionConforms to
public.data base type for any sort of simple byte stream, including files and in-memory data public.item
public.directory file system directory (includes packages AND folders) public.item
com.apple.resolvable anything the Alias Manager can resolve
public.symlink a symbolic link public.item, com.apple.resolvable
com.apple.mount-point a volume mount point (resolvable, resolves to the root dir of a volume) public.item, com.apple.resolvable
com.apple.alias-file a fully-formed alias file public.data, com.apple.resolvable
public.url The bytes of a URL public.data
public.file-url The text of a "file:" URL public.url
Text types
UTIDescriptionConforms to
public.text base type for all text-encoded data, including text with markup (HTML, RTF, etc.) public.data, public.content
public.plain-text text with no markup, unspecified encoding public.text
public.utf8-plain-text plain text, UTF-8 encoding public.plain-text
public.utf16-external-plain-text plain text, UTF-16 encoding, with BOM, or if BOM is not present, has "external representation" byte order (big-endian) public.plain-text
public.utf16-plain-text plain text, UTF-16 encoding, native byte order, no BOM public.plain-text
public.rtf Rich Text Format public.text
public.html HTML, any version public.text
public.xml generic XML public.text
public.xhtml XHTML public.xml
Composite content types
UTIDescriptionConforms to
com.adobe.pdf Adobe PDF public.data, public.composite-content
com.apple.rtfd Rich Text Format Directory (RTF with content embedding, on-disk format) com.apple.package, public.composite-content
com.apple.flat-rtfd Flattened RTFD (pasteboard format) public.data, public.composite-content
com.apple.webarchive The WebKit webarchive format public.data, public.composite-content
com.adobe.postscript PostScript public.data, public.composite-content
com.adobe.encapsulated-postscript Encapsulated PostScript com.adobe.postscript
public.presentation presentation public.composite-content
Image content types
UTIDescriptionConforms to
public.image abstract image data public.data, public.content
public.jpeg JPEG image public.image
public.jpeg-2000 JPEG-2000 image public.image
public.tiff TIFF image public.image
com.apple.pict Quickdraw PICT format public.image
com.compuserve.gif GIF image public.image
public.png PNG image public.image
com.apple.quicktime-image QuickTime image format public.image
com.apple.icns Apple icon data public.image
com.microsoft.bmp Windows bitmap public.image
com.microsoft.ico Windows icon data public.image
public.fax fax public.image, public.message
com.apple.macpaint-image MacPaint image public.image
public.svg-image scalable vector graphics (SVG) public.image
public.xbitmap-image X bitmap image public.image
public.camera-raw-image camera raw image public.image
com.adobe.photoshop-image Adobe Photoshop document public.image
com.adobe.illustrator.ai-image Adobe Illustrator document public.image
com.truevision.tga-image TGA image public.image
com.sgi.sgi-image Silicon Graphics image public.image
com.ilm.openexr-image OpenEXR image public.image
com.kodak.flashpix-image FlashPix image public.image
com.adobe.raw-image Adobe raw image public.camera-raw-image
com.canon.crw-raw-image Canon CRW raw image public.camera-raw-image
com.canon.cr2-raw-image Canon CR2 raw image public.camera-raw-image
com.canon.tif-raw-image Canon TIF raw image public.camera-raw-image
com.nikon.raw-image Nikon raw image public.camera-raw-image
com.olympus.raw-image Olympus raw image public.camera-raw-image
com.fuji.raw-image Fuji raw image public.camera-raw-image
com.sony.raw-image Sony raw image public.camera-raw-image
com.sony.arw-raw-image Sony ARW raw image public.camera-raw-image
com.konicaminolta.raw-image Minolta raw image public.camera-raw-image
com.kodak.raw-image Kodak raw image public.camera-raw-image
com.panasonic.raw-image Panasonic raw image public.camera-raw-image
com.pentax.raw-image Pentax raw image public.camera-raw-image
com.leafamerica.raw-image Leaf raw image public.camera-raw-image
com.leica.raw-image Leica raw image public.camera-raw-image
com.hasselblad.fff-raw-image Hasselblad FFF raw image public.camera-raw-image
com.hasselblad.3fr-raw-image Hasselblad 3FR raw image public.camera-raw-image
Audiovisual content types
UTIDescriptionConforms to
public.audiovisual-content audio and/or video content public.data, public.content
public.movie A media format which may contain both video and audio. Corresponds to what users would label a "movie". public.audiovisual-content
public.video pure video (no audio) public.movie
public.audio pure audio (no video) public.audiovisual-content
com.apple.quicktime-movie QuickTime movie public.movie
public.mpeg MPEG-1 or MPEG-2 movie public.movie
public.mpeg-4 MPEG-4 movie public.movie
public.mp3 MP3 audio public.audio
public.mpeg-4-audio MPEG-4 audio layer (.m4a) public.mpeg-4, public.audio
com.apple.protected-mpeg-4-audio Apple protected MPEG4 format (.m4p, iTunes music store format) public.audio
public.mpeg-2-video MPEG-2 video public.video
com.apple.protected-mpeg-4-video protected MPEG-4 movie public.movie
public.dv-movie DV movie public.movie
public.avi AVI movie public.movie
public.3gpp 3GPP movie public.movie
public.3gpp2 3GPP2 movie public.movie
com.microsoft.windows-media-wm Windows media public.movie, com.microsoft.advanced-systems-format
com.microsoft.windows-media-wmv Windows media public.movie, com.microsoft.advanced-systems-format
com.microsoft.windows-media-wmp Windows media public.movie, com.microsoft.advanced-systems-format
com.microsoft.windows-media-wma Windows media audio public.audio, com.microsoft.advanced-systems-format
com.real.realmedia RealMedia public.movie
com.real.realaudio RealMedia audio public.audio
public.ulaw-audio uLaw audio public.audio
public.au-audio AU audio public.audio
public.aifc-audio AIFF-C audio public.audio
public.aiff-audio AIFF audio public.aifc-audio
public.midi-audio MIDI audio public.audio
public.downloadable-sound downloadable sound public.audio
com.apple.coreaudio-format Apple CoreAudio format public.audio
public.ac3-audio AC-3 audio public.audio
com.digidesign.sd2-audio Sound Designer II audio public.audio
com.microsoft.waveform-audio Waveform audio public.audio
com.soundblaster.soundfont SoundFont audio public.audio
Directory types
UTIDescriptionConforms to
public.folder a user-browsable directory (i.e., not a package) public.directory
public.volume the root folder of a volume/mount point public.folder
com.apple.package a packaged directory public.directory
com.apple.bundle a directory conforming to one of the CFBundle layouts public.directory
Application types
UTIDescriptionConforms to
com.apple.application-bundle a bundled application com.apple.application, com.apple.bundle, com.apple.package
com.apple.application-file a single-file Carbon/Classic application com.apple.application, public.data
Contact types
UTIDescriptionConforms to
public.vcard VCard format public.data, public.contact
Archive types
UTIDescriptionConforms to
org.gnu.gnu-tar-archive GNU tar archive public.data, public.archive
public.tar-archive tar archive org.gnu.gnu-tar-archive
org.gnu.gnu-zip-archive GZip archive public.data, public.archive
org.gnu.gnu-zip-tar-archive gzip tar archive org.gnu.gnu-zip-archive
public.bzip2-archive Bzip2 archive public.data, public.archive
public.tar-bzip2-archive Bzip2 compressed tar archive public.bzip2-archive
com.apple.binhex-archive BinHex archive public.data, public.archive
com.apple.macbinary-archive MacBinary archive public.data, public.archive
com.allume.stuffit-archive Stuffit archive public.data, public.archive
public.zip-archive Zip archive com.pkware.zip-archive
com.pkware.zip-archive PKZip archive public.zip-archive
MS Office types
UTIDescriptionConforms to
com.microsoft.word.doc Microsoft Word document public.data, public.composite-content
com.microsoft.excel.xls Microsoft Excel workbook public.data, public.composite-content
com.microsoft.powerpoint.ppt Microsoft PowerPoint presentation public.data, public.presentation
com.microsoft.word.wordml Microsoft Word 2003 XML document public.xml, public.composite-content
iWork types
UTIDescriptionConforms to
com.apple.keynote.key Keynote document com.apple.package, public.presentation
com.apple.iWork.Keynote.key Keynote document com.apple.package, public.presentation, com.apple.keynote.key
com.apple.keynote.kth Keynote document com.apple.package, public.presentation
com.apple.iWork.Keynote.kth Keynote theme com.apple.package, public.composite-content, com.apple.keynote.kth
Office Open XML
UTIDescriptionConforms to
org.openxmlformats.openxml Office Open XML public.zip-archive
org.openxmlformats.wordprocessingml.document Office Open XML word processing document org.openxmlformats.openxml, public.composite-content
org.openxmlformats.wordprocessingml.document.macroenabled Office Open XML word processing document (macros enabled) org.openxmlformats.openxml, public.composite-content, public.executable
org.openxmlformats.wordprocessingml.template Office Open XML word processing template org.openxmlformats.openxml, public.composite-content
org.openxmlformats.wordprocessingml.template.macroenabled Office Open XML word processing template (macros enabled) org.openxmlformats.openxml, public.composite-content, public.executable
org.openxmlformats.spreadsheetml.sheet Office Open XML spreadsheet org.openxmlformats.openxml, public.composite-content
org.openxmlformats.spreadsheetml.sheet.macroenabled Office Open XML spreadsheet (macros enabled) org.openxmlformats.openxml, public.composite-content, public.executable
org.openxmlformats.spreadsheetml.template Office Open XML spreadsheet template org.openxmlformats.openxml, public.composite-content
org.openxmlformats.spreadsheetml.template.macroenabled Office Open XML spreadsheet template (macros enabled) org.openxmlformats.openxml, public.composite-content, public.executable
org.openxmlformats.presentationml.presentation Office Open XML presentation org.openxmlformats.openxml, public.presentation
org.openxmlformats.presentationml.presentation.macroenabled Office Open XML presentation (macros enabled) org.openxmlformats.openxml, public.presentation, public.executable
org.openxmlformats.presentationml.slideshow Office Open XML slide show org.openxmlformats.openxml, public.presentation
org.openxmlformats.presentationml.slideshow.macroenabled Office Open XML slide show (macros enabled) org.openxmlformats.openxml, public.presentation, public.executable
org.openxmlformats.presentationml.template Office Open XML presentation template org.openxmlformats.openxml, public.presentation
org.openxmlformats.presentationml.template.macroenabled Office Open XML presentation template (macros enabled) org.openxmlformats.openxml, public.presentation, public.executable
OASIS Open Document Format
UTIDescriptionConforms to
org.oasis-open.opendocument Open Document public.zip-archive
org.oasis-open.opendocument.text Open Document text org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.text-template Open Document text template org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.graphics Open Document graphics org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.graphics-template Open Document graphics template org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.presentation Open Document presentation org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.presentation-template Open Document presentation template org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.spreadsheet Open Document spreadsheet org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.spreadsheet-template Open Document spreadsheet template org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.chart Open Document chart org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.chart-template Open Document chart template org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.image Open Document image org.oasis-open.opendocument, public.image
org.oasis-open.opendocument.image-template Open Document image template org.oasis-open.opendocument, public.image
org.oasis-open.opendocument.formula Open Document formula org.oasis-open.opendocument, public.content
org.oasis-open.opendocument.formula-template Open Document formula template org.oasis-open.opendocument, public.content
org.oasis-open.opendocument.text-master Open Document text master org.oasis-open.opendocument, public.composite-content
org.oasis-open.opendocument.text-web Open Document HTML template org.oasis-open.opendocument, public.composite-content