System Font Replacement

This special Input Sans font package was originally designed to replace the Helvetica-based system font on Mac OS X 10.10 Yosemite. Like Input, it is available free of charge for private and unpublished use.



Please note: now that Apple has introduced the San Francisco font (a big improvement over Helvetica!), I may not be as zealous about tweaking these fonts for future versions of Mac OS. Get in touch for a beta version for Sierra.


Simply place the font files in /Library/Fonts. Log out and log back in for all changes to take effect.


To uninstall, remove the files from the /Library/Fonts directory. Log out and in again for all changes to take effect.

More Info

These special fonts contain metadata that allow them to masquerade as the system font family, and will not install like normal fonts. Installation is a nondestructive process: by placing the fonts in your /Library/Fonts folder, you can override the defaults without modifying system files or configuration. Simply remove these font files and everything goes back to normal.

This approach was inspired by Jens Kutílek’s Fira System Font Replacement.

These fonts have been scaled and adjusted to make them more suitable for use in Yosemite’s interface, and stem weights, letterspacing, and certain letterforms have been changed.

Known Issues

System font replacement is not perfect. Still it’s pretty amazing it works as well as it does.

Some apps, such as the App Store or Chrome, use the local copy of Helvetica or Helvetica Neue rather than the System Font. This means that you still might see bits of Helvetica pop up now and then. Such is life.

The vertical alignment of Chrome tab labels is too low. We haven’t found a way to repair this without creating other issues. If you are a big Chrome user, this fix will address this issue but will cause small alignment issues elsewhere.

baseline error

If the fast user switching menu is active, the vertical alignment of the username is also too low. Again, we haven’t found a way to repair this without creating other issues.

baseline error

There have been reports of unreadable placeholder glyphs appearing instead of text. First, make sure the fonts are installed in the top level /Library/Fonts directory instead of the user directory, as this will fix this problem in most instances. There have been reports of placeholders still showing up when changing system fonts or making in-app purchases. There is no known fix. Try logging out and back in, and if in doubt, uninstall the fonts. Or keep them, and you can think of it as extra security as you type in your password.

password error

Solved Issues

Download the latest version to address replacement issues in Messages and Firefox Developer Edition.

We previously recommended that you place fonts in your /User/Library/Fonts, which causes some security dialogs will appear as unreadable placeholder glyphs. To avoid this, move the fonts to your top level /Library/Fonts directory.

About Input

Input is a customizable typeface family designed for setting code and data, complete with Sans, Serif, and Monospaced versions in a variety of widths and weights. Read more about the full family, see it in action, and download it here.