The culture of the United States is primarily a Western culture, but is also influenced by Native American, African, Asian, Polynesian, and Latin American cultures. American culture started its formation over 10,000 years ago with the migration of Paleo-Indians from Asia into the region that is today the continental United States. It has its own unique social and cultural characteristics such as dialect, music, arts, social habits, cuisine, and folklore. The United States of America is an ethnically and racially diverse country as a result of large-scale immigration from many different countries throughout its history.

Its chief early European influences came from English, Scottish, Welsh and Irish settlers of colonial America during British rule. British culture, due to colonial ties with Britain that spread the English language, legal system and other cultural inheritances, had a formative influence. Other important influences came from other parts of western Europe, especially Germany, France, and Italy.

Original elements also play a strong role, such as the invention of Jeffersonian democracy. Thomas Jefferson's Notes on the State of Virginia was perhaps the first influential domestic cultural critique by an American and a reactionary piece to the prevailing European consensus that America's domestic originality was degenerate. Prevalent ideas and ideals that evolved domestically, such as national holidays, uniquely American sports, military tradition, and innovations in the arts and entertainment give a strong sense of national pride among the population as a whole.

American culture includes both conservative and liberal elements, scientific and religious competitiveness, political structures, risk taking and free expression, materialist and moral elements. Despite certain consistent ideological principles (e.g. individualism, egalitarianism, and faith in freedom and democracy), American culture has a variety of expressions due to its geographical scale and demographic diversity. The flexibility of U.S. culture and its highly symbolic nature lead some researchers to categorize American culture as a mythic identity; others see it as American exceptionalism.

It also includes elements that evolved from Indigenous Americans, and other ethnic cultures—most prominently the culture of African Americans, cultures from Latin America, and Asian American cultures. Many American cultural elements, especially from popular culture, have spread across the globe through modern mass media.

The United States has often been thought of as a melting pot, but beginning in the late 1990s and early 2000s, it trends towards cultural diversity, pluralism and the image of a salad bowl instead. Due to the extent of American culture, there are many integrated but unique social subcultures within the United States. The cultural affiliations an individual in the United States may have commonly depend on social class, political orientation and a multitude of demographic characteristics such as religious background, occupation and ethnic group membership.