If you are using a Mac with a Retina display (or a 4K display), you may have noticed that the text at the login screen can be really small after a reboot. For people with vision impairments it can be almost unusable. So I figured out a way to set the scaling for the login screen. The trick is to enable the root user and set the scaling to what you want.

The root user has permission to do anything. It’s extremely important you are aware of this. You can destroy your system if you do something wrong while logged in as root. Leaving it turned on poses a security risk. Make sure you disable it.

How to set the Scaling for the Login screen

  1. To login as the root user you need to enable it. If you don’t know how, follow Apple’s support article: Enabling and using the “root” user in OS X
  2.  Log out as yourself and log in as root.
  3.  Set the scaling for the root user to the way you want it displayed. Apple support article: Using a Retina display
  4.  Logout as root and repeat step 1 to disable root.
  5.  Reboot to test it. You should have a nicely scaled login screen now.