Part of Fortune calculator
The Part of Fortune is a calculated point, measured from the Ascendant by the distance between the Sun and Moon, and it is the best known of the classical lots.
Your birth details
It is not a planet and it does not move like one. The lot is an arithmetical point built from three positions in your chart, which is why it needs an exact birth time: it is measured from the Ascendant, and the Ascendant moves about a degree every four minutes.
The formula reverses with sect. In a day chart it is the Ascendant plus the Moon minus the Sun; in a night chart the Sun and Moon swap places. That is not a refinement, it is a reflection: the two results sit at equal distances from the Ascendant in opposite directions, so getting sect wrong does not nudge the point, it mirrors it. Our calculator establishes whether the chart is a day or a night one first, and tells you which formula it used.
Frequently asked
What is the Part of Fortune in astrology?
It is a calculated point, the best known of the classical lots, found by measuring the distance between the Sun and Moon and projecting it from the Ascendant. Traditional sources link it to the body, livelihood and the tangible side of fortune rather than to luck in the modern sense.
Why does the formula change for a night birth?
Because the lot is built from the two lights and the tradition reverses their roles by sect. In a day chart the Sun leads and the Moon is measured from it; at night the order swaps. The two versions land on opposite sides of the Ascendant, so it matters.
Do I need my exact birth time?
Yes. The lot is measured from the Ascendant, which moves roughly one degree every four minutes, so an hour of uncertainty moves the point by about fifteen degrees and can change its house.