Adult Broad-billed Sandpipers in summer plumage have blackish-brown upperparts with rusty edges of feathers. Crown is bordered by two narrow black strips and quite broad white supercilium. Lores is dark. The chin and throat are white; craw, fore-breast and flanks are brownish. Secondaries are with narrow white tips, inner secondaries are black, rusty-edged. Axillaries are white. Tail feathers are pale-brownish with narrow whitish tips; central pair of tail feathers is dark, blackish-brown. Bill is black. The form of bill is hard differs from form of bill of Calidris Sandpipers on whom Broad-billed Sandpiper is similar by habit; bill is quite broad and battered (in middle part bill's width is bigger than height), and dawn-turned in terminal part. Legs are dark, greenish. Eyes are dark-brown. In winter plumage of adult birds the edges of upperparts feathers are pale, whitish. Underparts are white with narrow dark streaks on throat, craw and fore-breast. Juveniles are similar on adults in summer plumage, but middle parts of upperpart feathers are pale-brownish. Underparts are white greyish-tinged on craw. Sizes: wing 95-110 mm, tarsus 20-25 mm, bill 28-36 mm.
"Птицы Казахстана" том 2. Алма-Ата, 1962.