Lot of Fortune Calculator — Part of Fortune & Hermetic Lots

The Lot of Fortune is the chief of the Hermetic lots — a point computed from your ascendant, Sun and Moon, not a planet. Ptolemy called it the 'lunar horoscope' (Tetrabiblos, III.10) and read it for the body, health and livelihood: the material circumstances of life. 'Part of Fortune' is simply another name for the same point — Western astrologers use the two terms interchangeably, and this calculator computes the one point under both names.

From the three anchors of the chart, combined as absolute positions in the tropical zodiac: for a day birth (Sun above the horizon at birth) Fortune = Ascendant + Moon − Sun; for a night birth Fortune = Ascendant + Sun − Moon. The result is a single degree in the zodiac, shown here with its exact position inside the sign and the whole-sign house it falls in. Your chart's sect — day or night — decides which formula applies, and the result card says which was used.

Because of sect — the day/night division at the heart of Hellenistic astrology. The tradition defines the lots so that Fortune keeps the Moon's sect and Spirit keeps the Sun's: by day the Moon is out of sect, by night it is in sect, and the formula flips to match. The practical consequence is that when the Sun is below the horizon at your birth, Fortune and Spirit swap formulas — a night birth's Fortune is computed with the day formula of Spirit, and vice versa.

The Lot of Spirit is Fortune's counterpart, always computed with the opposite formula. Where Fortune stands for the body and livelihood, Spirit stands for the mind, intention and career — the domain of the soul rather than the body, in the tradition's own framing. The same three points produce both lots, and the day/night rule assigns their formulas by sect; the two lots mirror each other around the ascendant, coinciding with it only when the Sun and Moon are conjunct — a new moon birth.

The Hermetic lots are a family of derived points described in the Hellenistic texts attributed to Hermes Trismegistus and used by Vettius Valens, Paulus Alexandrinus and others. Beyond Fortune and Spirit they include Eros (love and desire), Necessity (compulsion and obligation), Courage, Victory, Nemesis and more — each with its own classical formula built from the same anchors. This calculator shows every lot the engine computes, each with its sign, degree and whole-sign house.

The Hermetic lots are a Hellenistic, Western-tradition technique — classical Vedic astrology does not use the Part of Fortune at all, so there is no Jyotish equivalent to swap it for. This calculator works in the tropical zodiac (signs measured from the equinoxes), so every point on this page differs from a sidereal chart by the ayanamsa, currently about 24 degrees. If you are looking for the Vedic (sidereal) placements — the lagna, the rashi and the rest — use the Lagna Calculator instead.