Calmarza is a municipality in the province of Zaragoza, in the autonomous community of Aragon, Spain. It is located within the comarca of Comunidad de Calatayud, in the northwestern part of the province.
The municipality is sparsely populated, with a 2010 census recording 77 inhabitants. Like many villages in this part of rural Aragon, it has experienced a long-term decline in population as residents have moved to larger cities.
Calmarza sits in a hilly, semi-arid landscape typical of the Iberian System in this region, with the surrounding area characterized by limestone terrain, scrubland, and small valleys. The village is built around a compact historic core, and its economy has traditionally been based on agriculture, particularly dryland farming and livestock.