Calw is a Landkreis (district) in the middle of Baden-Württemberg, Germany.

Neighboring districts are (from north clockwise) Karlsruhe, Enz, the district-free city Pforzheim, Böblingen, Freudenstadt and Rastatt.

The district belongs to the northern part of the Black Forest mountains.

The coat of arms, which is nearly identical to the coat of arms of the city Calw, shows the lion of the Counts of Calw on top of three mountains.

(The latter two cities are not part of the present-day district of Calw) The fountain in the bottom represents the springs and spas in the district.