Vratव्रत

A Vrat is a religious vow or fast observed on a specific day, usually tied to a particular weekday, Tithi, or deity (e.g. a Thursday fast for Brihaspati/Vishnu, or Ekadashi fasting).

In practice

If a Vrat is listed for the day, it names the specific fast/observance traditionally associated with that day and a one-line note on which deity or purpose it serves.

How it's calculated

Weekday- and Tithi-based lookup; no astronomical calculation involved beyond determining the day itself.