Kaushitaki Brahmana Upanishad is an ancient Sanskrit text contained inside the Rigveda. It is associated with the Kaushitaki shakha. The chronology of Kaushitaki Upanishad, like other Upanishads, is unclear. It is based on an analysis of archaism, style and repetitions across texts, driven by assumptions about likely evolution of ideas, and on presumptions about which philosophy might have influenced which other Indian philosophies.