Fira System Font Replacement

Though you can’t choose any font you wish, you can use these modified Fira Sans fonts to replace Mac OS X Yosemite’s default System Font. Best of all, it’s easy to do and involves absolutely no hacking of system files.

  1. First, download Fira System Font Replacement.
  2. Next, drop the fonts into your /Library/Fonts folder. Note that this is not your User Library folder, but the one you see at the root level of your storage drive.
  3. Now simply relaunch the Finder. To do that, Option+Click the Finder icon in the Dock and choose “Relaunch” from the menu.

You should immediately see the new font appear in all your windows and menus. If you don’t like Fira Sans as the system font, you can simply remove the fonts from the Fonts folder and relaunch the Finder again.

As I stated at the start, this won’t work with just any font. This version of Fira Sans has been altered to supersede Apple’s default system font. The original system fonts haven’t been touched, which is why you can switch back simply by removing the Fira Sans.

These fonts are intended as a system font replacement on Mac OS X 10.10 Yosemite. They are based on the Fira Sans font family by Erik Spiekermann and Ralph du Carrois, and are licensed under the Open Font License version 1.1 or later. The System font replacement package has been prepared by Jens Kutilek.