• What is a UTI?
• Where can I find lists of UTIs?
• How can I know the UTI of a given file?
• Can I list all UTIs on my system?

What is a UTI

A Uniform Type Identifiers (UTI) is string identifing a type of data.

SpotLook tracks uses UTIs to know what to find.

Here are some UTIs for instance:

See also:

• http://en.wikipedia.org/wiki/Uniform_Type_Identifier
• http://developer.apple.com/documentation/Carbon/Conceptual/understanding_utis/utilist/chapter_4_section_1.html

Where can I find lists of UTIs

• http://developer.apple.com/documentation/Carbon/Conceptual/understanding_utis/utilist/chapter_4_section_1.html
• http://developer.apple.com/documentation/AppleApplications/Conceptual/AutomatorConcepts/Articles/AutomatorPropRef.html
• http://www.huw.id.au/filetypes.html
• http://kevin.sb.org/2006/03/16/graph-of-all-universal-type-identifiers/

Kevin Ballard posted an autogenerated GraphViz file showing all the Uniform Type Identifiers present on his system. I don't know how he did this, he did not post his ruby script. But for the ones who don't have GraphViz, you can download the resulting PDF file here: utigraph.pdf.

How can I know the UTI of a given file

If you have a file and you wonder what is its UTI, you can use the command-line tool mdls.

$ mdls AppleGaramond.ttf
kMDItemContentTypeTree         = (
    "public.truetype-ttf-font",
    "public.truetype-font",
    "public.font",
    "public.data",
    "public.item"
)

In this example, we will find AppleGaramond.ttf by searching for any of the UTIs of the hierarchy.

Can I list all UTIs on my system

Yes, use menu Tracks > UTI Discoverer…

See also http://seriot.ch/software_cli.php#utis for a Python script.