Accelerationism is a range of Marxist and reactionary ideas in critical and social theory that call for the drastic intensification of capitalist growth, technological change, infrastructure sabotage, and other social processes in order to destabilize existing systems and create radical social transformation, otherwise known as "acceleration". The term also refers to the post-Marxist idea that because of capitalism's internal contradictions and instabilities which can jeopardize its growth, the abolition of the system and its class structures could be brought about by its acceleration. Various ideas, including Gilles Deleuze and Félix Guattari's idea of deterritorialization, Jean Baudrillard's proposals for "fatal strategies", and aspects of the theoretical systems and processes developed by English philosopher, and later Dark Enlightenment commentator, Nick Land, are crucial influences on accelerationism, which aims to analyze and subsequently promote the social, economic, cultural, and libidinal forces that constitute the process of acceleration.

Accelerationism has since been taken as an ideological spectrum divided into mutually contradictory left-wing and right-wing variants. Both support the indefinite intensification of capitalism and its structures as well as the conditions for a technological singularity, a hypothetical point in time where technological growth becomes uncontrollable and irreversible.

However, the term has, in a manner strongly distinguished from original accelerationist theorists, been used by right-wing extremists such as neo-fascists, white nationalists and white supremacists to increasingly refer to an "acceleration" of racial conflict through assassinations, murders and terrorist attacks as a means to violently achieve a white ethnostate.