How many days after Dussehra is Diwali celebrated?

Diwali is celebrated exactly 20 days after Dussehra is celebrated, which is usually in the month of October or November. According to the Hindu epic Ramayana, Dussehra is the day that celebrates a victory of good over evil: marking the day Lord Ram killed the evil king of Lanka, Ravan. Diwali is the festival of lights and it celebrates the beginning of a new year.