Monthly 8th day of Krishna Paksha dedicated to Kala Bhairava, a fierce form of Lord Shiva.

Kalashtami falls on the Ashtami of Krishna Paksha each month and is dedicated to Kaal Bhairav, the fierce guardian form of Shiva who governs time itself. Bhairav is the kotwal — the divine police chief — of Kashi, and no pilgrimage to that city is complete without his darshan. He is invoked against fear, enemies, litigation, black magic, chronic obstacles and the harsher effects of Rahu, Ketu and Shani. Because Bhairav rules time, worship on this day is believed to remove delays: stalled work, blocked money, and matters stuck in courts or bureaucracy. His vahana is the dog, and feeding dogs on Kalashtami is considered as meritorious as the puja itself.

A day-long fast is kept and broken the following morning. Some observe only a partial fast, taking one satvik meal after the evening puja.