Look for the rusty cap first. A breeding Chipping Sparrow adds a pale eyebrow, a black line through the eye, and clean gray-white underparts; its gray rump is a useful flash in flight. 1

This is a slender, fairly long-tailed sparrow measuring 4.7-5.9 inches (12-15 cm), with an 8.3-inch (21 cm) wingspan. It feeds on the ground, then often lifts in a direct, undulating flight. 2

The song is a thin, flat one-note trill, like a tiny sewing machine. Listen high in small trees and evergreens, where males sing from exposed outer branches in spring and summer. 3 2

For the fast comparison: Field Sparrow has a white eyering and pink bill, while American Tree Sparrow is plumper with a bicolored bill and a common dark central breast spot. 4 5