This site contains tools to calculate panchang and muhurta. The position of the planets are calculated with the lahiri ayanamsa and the months are calculated from amavasya.
A panchang is an Indian calendar which has traditional units of timekeeping based on the position of both the sun and moon. Western calendars are only based on the position of the sun. From the position of the sun and moon, five different attributes of time are calculated and displayed on the calendar.
The five attributes of time are: