There are lots of links to the Disney World Parks Pass Availability Calendar floating around without the full set of parameters. I’m putting this here mostly for my usage, but in case you need it, the availability calendar, WITH BUTTONS to allow you to browse all three sets of color-coded availability, is here:
https://disneyworld.disney.go.com/availability-calendar/?segments=tickets,resort,passholder
Also, you can learn more about the Disney World Parks Pass System here.