How we calculate

We use the tropical zodiac: 0 degrees Aries begins at the spring equinox. No sidereal correction is applied.

We use Placidus houses, the system most astrologers work with today. The house cusps are calculated from the exact birth time and place by dividing the daily arcs of the sky into thirds. Beyond the polar circles Placidus cannot be calculated; there we use Whole Sign houses.

Sun and Moon are calculated with analytical series from Jean Meeus, Astronomical Algorithms. The planets use NASA JPL approximate orbital elements, which are designed for the years 1800 to 2050. That is why charts can currently be calculated for birth dates from 1900 to 2050. Chiron uses simplified orbital elements and is accurate to about one degree.

The Lunar Nodes are the true (osculating) nodes. Black Moon Lilith is the mean lunar apogee.

Birth chart: conjunction and opposition 8 degrees, square and trine 7, sextile 5, quincunx 3, semi sextile 2. Compare with Crush: 8, 8, 6, 6 and 4 degrees. Transits: 2 degrees for Mars, Jupiter and Saturn, 1.5 degrees for Uranus, Neptune and Pluto.

The Ascendant, the MC and all houses depend on the exact birth time. Without a birth time we calculate for noon, do not show houses, Ascendant or MC and leave the Moon out wherever its sign could be uncertain.

Your birth time is converted to universal time with the time zone of your birthplace, including historical daylight saving time, using your browser's time zone database.

The 64 gates are arranged around the tropical zodiac. Gate 41 begins at 2 degrees Aquarius. Each gate covers 5.625 degrees and each of its six lines 0.9375 degrees.

The Personality is calculated for your moment of birth. The Design is calculated for the moment when the Sun stood exactly 88 degrees before its birth position, about three months before birth.

On each side we use 13 activations: Sun, Earth, Moon, North and South Node (true node) and Mercury to Pluto. A channel is defined when both of its gates are activated, and a center is defined when it is part of a defined channel.

No defined center: Reflector. Defined Sacral: Generator, or Manifesting Generator when a motor center connects to the Throat. Undefined Sacral: Manifestor when a motor connects to the Throat, otherwise Projector. The motors are the Heart, Sacral, Solar Plexus and Root.

We follow the classical order: Solar Plexus (emotional), Sacral, Spleen, Heart (ego), G center (self projected), then mental or environmental authority. Reflectors have lunar authority.

The Moon changes gate roughly every ten hours and the lines change even faster. An inaccurate birth time can shift lines, your profile or, near a boundary, a gate. Please enter your birth time as precisely as you can.

The Guidance Studio uses Pythagorean numerology: A, J, S = 1, B, K, T = 2, and so on up to I, R = 9.

We add all digits of your full birth date (day, month and year together) and reduce the sum. The master numbers 11, 22 and 33 are not reduced further. Other schools reduce day, month and year separately first, which can occasionally give a different result.

Accents and umlauts are removed (é becomes E, ü becomes U), ß becomes SS, and spaces and hyphens are ignored. Only letters of the Latin alphabet are counted, so names in other scripts need to be entered in Latin letters.

Only A, E, I, O and U count as vowels for the Soul Urge number. Y is always treated as a consonant and counts toward the Personality number.

Personal Year: birth day plus birth month plus the calendar year in which your last birthday fell, reduced to one digit. Personal Month and Personal Day build on it. Your Personal Year changes on your birthday.

Your year, month, day and hour pillars are calculated with the BaZi method from the ten heavenly stems and twelve earthly branches.

In BaZi the year begins at Li Chun, when the Sun reaches 315 degrees, around 4 February. The year table on the website additionally shows the Chinese New Year, which follows the lunar calendar and can fall on a different day.

The month pillar changes at the twelve solar terms that start the months, calculated from the actual position of the Sun.

The day pillar follows the continuous sixty day cycle and changes at local midnight. The hour pillar uses the double hours of your local clock time; the late Rat hour from 23:00 to midnight still belongs to the current day.

We use the clock time you enter in the time zone of your birthplace. True solar time and daylight saving adjustments to the hour pillar are not applied. Some schools do adjust for them, so the hour pillar can differ from other calculators near a boundary.