Calkin or calkins may refer to:

a Caulkin, part of a horseshoe

Geography Calkin Glacier, a glacier west of Sentinel Peak, flowing north from the Kukri Hills in Victoria Land, Antarctica

Mathematics In functional analysis, the Calkin algebra, named after John Wilson Calkin The Calkin–Wilf tree in number theory

People Calkin (surname) Calkins (surname)

Other uses Calkins Media, a media company based in Levittown, Pennsylvania C.C. Calkins, a small steamboat built in 1890 which served on Lake Washington