Janma Tithi

What a Tithi Is

A tithi is a lunar day, and it is defined by geometry rather than by the clock. It is the period during which the angular distance between the Moon and the Sun increases by exactly twelve degrees.

Because the Moon moves at varying speed, a tithi is not a fixed length — it can run anywhere from roughly nineteen to twenty-six hours. That is why a tithi does not line up neatly with a calendar day, and why a tithi can occasionally be skipped or repeated.

Shukla and Krishna Paksha

The lunar month divides into two halves of fifteen tithis each. Shukla Paksha is the waxing half, running from the new moon to the full moon, when the Moon is moving ahead of the Sun and growing. Krishna Paksha is the waning half.

The fifteenth tithi of Shukla Paksha is Purnima, the full moon. The fifteenth of Krishna Paksha is Amavasya, the new moon.

The Five Tithi Groups

The fifteen tithis fall into five families of three, and these are used more in date selection than in birth chart reading.

Nanda (1, 6, 11) is associated with joy and celebration, considered favourable for beginnings and social occasions.

Bhadra (2, 7, 12) is associated with prosperity and steady growth, favoured for work, trade and building.

Jaya (3, 8, 13) is associated with victory and effort rewarded, favoured for competition.

Rikta (4, 9, 14) is traditionally considered less favourable for beginnings, and better suited to clearing and completing.

Purna (5, 10, 15) is associated with completion and fullness.

Where Tithi Actually Matters

Its main use is muhurat — choosing a date for a marriage, a griha pravesh, a business launch or any significant beginning. Tithi is one of the five elements of the panchang, alongside the nakshatra, the vara or weekday, the yoga and the karana.

In birth chart reading it plays a smaller role than the nakshatra, which is what drives the Dasha system, naming and matching. But your janma tithi recurs each lunar month, and some families observe it rather than the solar birthday.

Why a Tithi Alone Is Not a Muhurat

This is the distinction worth carrying away, because it explains the difference between a free panchang app and a proper date selection.

A generic panchang tells you which tithi and nakshatra fall on a given day, which is genuinely useful information. A muhurat weighs those against the ascendant rising at the specific hour, the planetary positions at that moment, and the birth chart of the person the event is for.

That is why two families can be given different dates in the same month for the same kind of event, and why a date that is generally auspicious may not be the right one for a particular person.