Size
Finches are passerine (perching) birds with short beaks and average from 4 to 6 inches in length (12 to 16 cm). The pine grosbeak is an exception and has been measured at 9 inches (23 cm).
Flight
"Winter finches" have been known to meander south one season and then north the next, and so could be said to have an erratic wintering range. The common redpoll may breed as far north as the Arctic, and the lesser goldfinch as far south as Mexico.
Location
Many finches may not vary their location much at all; the Red Crossbill, White-winged Crossbill and House Finch maintain a steady year-round range.
Yellow
Those that can be categorized into yellow finches are the pine siskin, American goldfinch, lesser goldfinch, Lawrence's goldfinch, evening grossbeak and Oriental greenfinch.
Red
Those that can be categorized into red goldfinches are the common redpoll, hoary redpoll, rosy finch, purple finch, Cassin's finch, house finch, common rosefinch and Eurasian bullfinch.
Beaks
Fringillids are distinct in that they have what bird expert Don Robertson describes as "stout, conical bills," and tough skulls, jaws and tongues that aid in shelling seeds.
