Is there a method for associating file types with applications via terminal? I thought ~/Library/Preferences/com.apple.launchservices.plist might do it, and I also have seen: Why is a command line change to ~/Library/Preferences/com.apple.LaunchServices.plist not effective immediately? but I can't seem to get it working.

I guess I'm looking for a way to imitate what the GUI does when someone uses it to change association types, it seems to work instantly there...


4 Answers 4


You can edit ~/Library/Preferences/com.apple.LaunchServices.plist (~/Library/Preferences/com.apple.LaunchServices/com.apple.launchservices.secure.plist on Catalina) in a text editor after converting it to XML:

plutil -convert xml1 ~/Library/Preferences/com.apple.LaunchServices.plist
# Catalina: 
plutil -convert xml1 ~/Library/Preferences/com.apple.LaunchServices/com.apple.launchservices.secure.plist -o output.xml

Then add entries like this to the LSHandlers array:


You can use mdls to see the UTIs of file types and something like osascript -e 'id of app "AppName"' to see the bundle identifiers of applications.

You can apply changes to com.apple.LaunchServices.plist by restarting. Logging out and back in isn't enough.

NOTE: duti is no longer in active development and has been labeled by its maintainers as "unsupported". The project hasn't seen any major progress since 2012 aside from configuration updates. It has moved from Sourceforge to Github. This answer has been updated to include the new links.

I also use duti though. I have saved a file like this (with about 100 lines) as ~/.duti:

org.gnu.Emacs public.plain-text all # .txt, .text, plain text files without an extension
org.gnu.Emacs public.unix-executable all # executable scripts
com.SequentialX.Sequential .jpg all
org.videolan.vlc .mkv all

I have a launchd agent that runs duti ~/.duti automatically when ~/.duti is changed.

You can normally use filename extensions (like .jpg) instead of a UTIs (like public.jpg) to specify file types. duti converts the extensions to UTIs that also apply to other extensions (like .jpeg). For some extensions like .mkv and .tex, the UTI depends on what application registered the extension first.

The latest version of duti only includes source code, but 1.5.0 also includes an installer.

  • duti is well maintained as I see it. There is nowadays also a shell wrapper which helps to associate the applications very well, it's linked in the README of duti. duti + dutis rocks :)) Commented Mar 13 at 11:54

Check out duti:

duti is a command-line tool written by Andrew Mortensen, designed to set default applications for document types and URL schemes on Mac OS X.

Document types on Mac OS X are defined by what Apple calls Uniform Type Identifiers, or UTIs. HTML files, for example, have a UTI of public.html. Microsoft Word documents are described by the UTI com.microsoft.word.doc. Apple provides many UTIs with Mac OS X, but developers are free to define their own, as long as the UTI is unique to that document type.

duti's name means "default for UTI."

  • 9
    Mandatory suggestion: use brew install duti to install duti Commented Jun 4, 2017 at 14:03
  • Use, for example, osascript -e 'id of app "Visual Studio Code"' to get the bundle ID of an application. Also, man duti shows the manual page for duti.
    – N4v
    Commented Jul 6, 2023 at 12:56

Here is a launchd agent for duti that will do the trick:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">

Obviously replace joshgummersall with your own username. I placed this file at ~/Library/LaunchAgents/duti.plist, chmmodd to 644 and ran:

$ launchctl load -F -w ~/Library/LaunchAgents/duti.plist

Short answer: A file's application association is stored in the file's resource fork, and Apple provides two utilities (Rez and DeRez) which allow manipulation of resource forks., but this is not for the faint of heart.

For more details, this question is answered very thoroughly at Super User:

  • Nowadays, it's in an extended attribute (xattr) named com.apple.LaunchServices.OpenWith Commented Apr 24, 2023 at 9:19

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