The Danish Realm, officially the Kingdom of Denmark, or simply Denmark, is a sovereign state and refers to the area over which the monarch of Denmark is head of state. It consists of metropolitan Denmark—the kingdom's territory in continental Europe and sometimes called "Denmark proper" (Danish: egentlige Danmark)—and the realm's two autonomous regions: the Faroe Islands in the North Atlantic and Greenland in North America. The relationship between the three parts of the Kingdom is also known as The unity of the Realm.

The Kingdom of Denmark is not a federation; it is a concept encompassing the three autonomous legal systems of Denmark, the Faroe Islands and Greenland, united under its monarch. The Kingdom of Denmark is a unitary sovereign state. It has Arctic territorial claims in the Arctic Ocean: various sites near the North Pole (Lomonosov Ridge, Gakkel Ridge, Alpha-Mendeleev Ridge complex, and the Chukchi Borderland). Constitutionally, the Kingdom of Denmark encompasses the realm or the country, but the Faroe Islands and Greenland have an extended degree of autonomy to govern their relations.

The Faroe Islands and Greenland have been under the Crown of Denmark since 1397 (de facto) when the Kalmar Union was ratified, and part of the Danish Realm since 1814 (de jure). However, due to their separate historical and cultural identities, these parts of the Realm now have an extensive degree of self-government and have assumed legislative and administrative responsibility in a substantial number of fields.

Legal matters in the country or realm are subject to the Constitution of the Realm of Denmark. It stipulates that it applies for all parts of the Kingdom of Denmark and that legislative, executive and judicial powers are the responsibility of the Parliament of the Kingdom of Denmark (Danish: Folketing), the Government of Denmark and the Supreme Court of Denmark. The Faroe Islands were granted home rule via an independence referendum in 1946, and Greenland did so in a 1979 referendum. In 2005, the Faroes received a self-government arrangement, and in 2009 Greenland received "self rule", thus leaving the government of Denmark with little influence over the matters of internal affairs that are devolved to the local governments of Greenland and the Faroe Islands.

The country or realm has land borders with Germany (the Danish-German border) and Canada (Hans Island), and a road and rail bridge-tunnel that connects to Malmö, Sweden (the Danish-Swedish border).