Ajivika (Sanskrit: आजीविक, IAST: Ājīvika) is an ancient nāstika, or 'heterodox,' Indian school of absolute fatalism or extreme determinism. The Ājīvika school is known for its Niyati ("Fate") doctrine and for the premise that there is no free will, that everything that has happened, is happening and will happen is entirely preordained and a function of cosmic principles.
Believed to have been founded in the 5th century BCE by Makkhali Gosāla, it was a Śramaṇa movement and a major rival to other contemporary orthodox and heterodox movements within the Indian philosophical milieu. Ājīvikas were organized renunciates who formed discrete communities. The precise identity of the Ājīvikas is not well known, and it is even unclear if they were a divergent sect of the Buddhists or the Jains.