Install Zebra ZD421 on Mac

On the Mac where you want to install the Zebra printer, open a web browser and go to: http://localhost:631.

If you can not access http://localhost:631 you might ned to enable the CUPS Web Interface. Open Terminal and run: cupsctl WebInterface=yes

Then reconnect to: http://localhost:631

Add Printer
Go to: Administration → Add Printer

Select Connection Type
Choose: AppSocket/HP JetDirect

Enter Printer Address

Enter the printer’s IP address.
Example (printer IP: 192.168.1.10): socket://192.168.1.10:9100

Name the Printer
Name: Zebra-ZD421
Description: Zebra ZD421
Location: My Office

Select Manufacturer
Choose: Zebra
Click Continue

Select Driver
Choose: Zebra ZPL Label Printer (en)
Click Add Printer

Configure Label Settings
Here is the settings I use for my media.
• Media Size: Custom
• Width: 102 mm
• Height: 192 mm
• Units: Millimeters
• Resolution: 203 dpi
• Media Tracking: Non-continuous (Web sensing)
• Media Type: Printer Default
Click: Set Default Options

(Optional) Disable the Web Interface

If you enabled the CUPS Web Interface earlier, you can disable it again by running the following command in the Terminal: cupsctl WebInterface=no