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Lesser Goldfinch
lesser goldfinch
Steve Byland / Shutterstock
The lesser goldfinch is the smallest North American finch of the Spinus genus. It may very well be the smallest true finch in the entire world, growing to an average of just 3.5 to 4.7 inches in length. The Andean siskin may beat it by a feather for the title, though, as it comes in at an average of 3.7 to 4.3 inches in length. Still, the goldfinch is truly minuscule. It weighs around 0.28 to 0.41 ounces.