Neil Turner's Blog

Blogging about technology and randomness since 2002


Apple’s introduction of Universal Binaries – programs which can run on both PowerPC and Intel architectures – was, on the whole, a good idea: consumers didn’t have to ensure they had the right version or know what type of processor their Mac had. But the big disadvantage was that this meant including compiled code for both architectures, which basically doubles the size of each application.
Enter Trimmit. Trimmit will cut your applications down to size by safely removing the architecture that isn’t needed by your computer. So, if you have an Intel Mac, it’ll cut out the PowerPC code, and vice versa. It will also remove various junk files and debug symbols, compress any TIFF images included in them, remove any language translations other than your own and do some general cleaning.
To give you some idea of the potential space savings, I ran it over Microsoft Messenger:mac and decreased the application size from 24.3 MB down to 11 MB. Similar savings where made with other programs.
Obviously an application like this is not without risks – some programs run integrity checks to ensure they haven’t been modified and will refuse to run if they have had their guts stripped out. Others may work in strange ways. Trimmit thankfully backs up all programs that are trimmed but it’s worth verifying that they work after their surgery. There’s also not a lot of point running it on programs that you update frequently as you’ll have to run Trimmit each time you update, potentially decreasing any space savings.
But for those stuck for hard drive space, Trimmit may offer some welcome relief.


  1. If you use it in default mode then doesn’t the Trimmit actually increase your disk space requirement? In your example instead of requiring 24.3 MB for the none Trimmit’ed app you need 34.3 MB instead?

  2. If you wanted to keep both the trimmed and non-trimmed apps, then yes, it would increase the requirement, but the idea is that you check to see if the newly-trimmed application works and then delete the untrimmed one. Thusly:
    Application X untrimmed: 24.3 MB
    Application X trimmed and untrimmed: 35.3 MB
    Application X after untrimmed copy deleted: 11 MB
    Does that make sense?