this is a medium-sized swift, measuring from in length, with a wingspan of and a weight ranging from . the sexes are identical in plumage, though males average slightly heavier than females. the adult's plumage is a dark sooty olive above and grayish brown below, with a slightly paler rump and uppertail covert feathers, and a significantly paler throat. its upperparts are the most uniformly colored of all the "chaetura" swifts, showing little contrast between back and rump. its beak is black, as are its feet and legs. its iris is dark brown. juvenal plumage (that held by juvenile birds) is very similar to that of adults, but with whitish tips to the outer webs of the secondaries and tertials.