Kayastha a sub-caste of Hindus, also known as Karana-Kayastha, which emerged as a huge sub-caste in Bengal during the 9th-11th centuries AD. Mention has been made of a class of people known as Kayastha in ancient scripts of Bengal, where they have been treated as Karana or Kayastha, writer or accountant. Vaijayanti (11th century), a lexicographer, mentioned Karana and Kayastha as writers. In Vrihaddharma Purana, Karana and Kayastha are synonymous. They acknowledge Chitragupta as their progenitor.

A sub-caste, their position in Bengal is after the Brahmans. Common Kayastha names include Chanda, Gupta, Nag, Aditya, Nandi, Mitra, Sil, Dhar, Kar, Datta, Rakshit, Dev, Palit, Ghosh, Bose, and Guha. However, many people of other sub-castes also sometimes use these surnames nowadays.

In Bengal and elsewhere, Kayasthas form a developed and affluent class whose contributions to arts, crafts, science, literature, economics, education and social development are noteworthy. Their religious and social activities are like those of the general Hindus. [Hiralal Bala]