I have a 96 sq ft run & a 25 sq ft coop for a total of 10 birds (4 standard chicks, 4 bantum chicks, & 2 mallards). It leaves me enuf room to add 1-2 more birds depending on what they are. So you just have to calculate how many birds you have & how many you may want to add & go from there. They say 4 sq feet of coop for standard chicks, 2 for bantums, 4 for small ducks & 6-8 for large ducks. Run should be 10 sq ft for each standard chick, 5 for bantums, 6-8 for small ducks & 10-12 for large ducks. My coop is actually a bit small if my mallards decide they want in too but I'm looking at building them their own dog-box style coop at ground level since I have heard ducks prefer lower nesting areas. Right now the size isn't really an issue cuz they are all only about 4 weeks old.
