Run two instances of Unity with one easy button

@TornadoTwins had asked publicly how to run two instances of Unity on a single machine. With Unity 3, it’s very simple. All you need to do is run Unity via Terminal. Some users, however, shy away from Terminal and would like a way to launch two (or more) instances without touching a command line. Follow these steps and you will create your own app launcher capable of opening as many instances as you’d like.

  1. Open Automator, located in your Applications folder.
  2. Create a new Workflow and drag the “Run Shell Script” action into your workspace.
  3. Type the following into the text box: /Applications/Unity/
    Note that if you installed Unity to a different location, you will need to edit the text to match. After this step, your view should look like this:
  4. Go to File -> Save As and choose type Application. Choose a name and save to a location on your computer. This step should look like:
  5. Drag this newly created .app into your dock and click away! You should be able to open multiple Unity instances. Note that on my machine, the LaunchUnity application was not quitting itself properly so you may have to quit the LaunchUnity app before clicking on it to launch your second instance.

See updated comments for two alternative ways (using Terminal) to achieve this result.


  1. Alternate method #1 – Another way to do it as a one-click button would be to create a non-rich text file (simple .txt) containing the line (/Applications/Unity/ and save it to a file with the extension “.command”. OSX reads this shell script as an executable command but is not given execute permissions by default. One would then have to open up terminal, and chmod +x the file, thus giving it execute permissions. Then, it could be launched just like the .app created with Automator. Since Automator comes with every and is drop dead simple, it seemed better to explain it that way.

    Alternate method #2, provided by AngryAnt – “To force new app instances, you could also simply pass -n to the open terminal command” This indeed does work, shortening the Terminal command to “open -na Unity”. I wonder how this copes with multiple installs of Unity in the Applications folder.

  2. You’re a genius!!!
    Thanks so much for writing this down.
    Sooo…. why aren’t you selling on yet? We need more skilled gamedevs with German last names!!


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