According to the 2011 Census of India, Kalpeni had a population of 4,319, though this number has experienced modest natural growth in the years since. The population is remarkably homogeneous, with almost 100% of the residents adhering to Sunni Islam.
The people of Kalpeni belong to the broader ethnic and linguistic group of Malayalis, and Malayalam is the primary language spoken, albeit with a distinct local dialect. Kalpeni boasts a high literacy rate, reflecting the Union Territory's broader emphasis on education. Culturally, the island is noted for its adherence to a matrilineal kinship system known as *Marumakkathayam*—a cultural import from Kerala's ancient Nair communities—where descent and property inheritance are traced through the mother's line.
