Wikipedia
Kulkarni is a Brahmin family name native to the Indian state of Maharashtra and northern Karnataka.
The name Kulkarni is believed to be a combination of two words (kula and karani). Kula means the root of the family, and Karanika means one who maintains records or accounts. Traditionally, Kulkarni was a title used for people who used to maintain the accounts and records of the villages and used to collect taxes. The title of the Kulkarni was later replaced by the Talathi. The Pargana and Kulkarni Watans were abolished in 1950.
Most Kulkarnis belong to the oldest Brahmin caste of Maharashtra and Karnataka, the Deshastha Brahmins. The surname is also found amongst Karhade Brahmin, and the Chandraseniya Kayastha Prabhu, Goud Saraswat Brahmin and Daivajna communities. Also Kulkarni is a common surname among Vaisnavas, Madhwa Brahmins & Shivalli Smarta Brahmins.
Kulkarni families who hail from Maharashtra speak Marathi and Konkani. In Northern Karnataka families speak Kannada and Konkani. Most Kulkarni families originate from Maharashtra or northern Karnataka but in more recent times migrated and settled all over the world.