Free Self-Discovery Tool
Free Big 3 calculator. Your Sun and Moon sign from your birth date, no birth time needed, with the exact minute on cusp days. Add your time and place for your Rising sign.
All three come from the same chart math. The Sun’s and Moon’s ecliptic longitudes are computed with the Swiss Ephemeris for your birth instant in the tropical zodiac, and each 30-degree segment names the sign. The Rising sign is the degree of the ecliptic crossing the eastern horizon at your birth time and place, which is why it needs the time and the coordinates while the Sun and Moon mostly do not.
A calendar date is not one instant. Across the inhabited time zones, from UTC+14 to UTC-12, "born on March 14" spans about 50 hours of universal time. This calculator samples the Sun and the Moon across that whole span. When every sample lands in one sign, the answer is certain for anyone born on that date anywhere on Earth. When a body crossed into a new sign inside the span, you see both signs and the crossing minute instead of a guess, and your own birth time and place decide which side you fall on.
The Sun is what you are building, the Moon is what you need while you build it, and the Rising sign is the door you walk through to do it. The three often sit in different elements: a fire Sun with a water Moon and an air Rising reads very differently from three earth signs. The full birth card below shows the house each one occupies and a reading written from the whole chart, where the Big 3 become the frame rather than the whole picture.
Your Sun sign, your Moon sign, and your Rising sign (the Ascendant). The Sun is identity and purpose, the Moon is emotional needs and instinct, and the Rising sign is the sign on the eastern horizon at the minute you were born: how you meet the world, and the point that starts your 1st house.
Two of the three. The Sun stays in each sign for about a month, so your birthday settles it on all but the one or two days a year it changes sign, and on those days we show the exact crossing minute. The Moon changes sign every two to three days, so on most birthdays it was in one of two signs somewhere on Earth: the quick answer shows both and the minute it moved, and your birth time and place settle it. The Rising sign changes about every two hours and always needs your time and place.
Speed. The Sun moves about one degree a day and changes sign twelve times a year. The Moon moves about thirteen degrees a day and changes sign roughly 160 times a year, once every two to three days. A calendar date covers about 50 hours across the world’s time zones, and in 50 hours the Moon travels close to a whole sign, so the date alone often leaves two possibilities.
From your exact birth time, date, and place: it is the zodiac sign rising on the eastern horizon at that minute at that location. This calculator computes it with the Swiss Ephemeris, the same engine as the full birth chart. The Rising sign does not depend on the house system you choose.
Yes. No account is needed for the quick answer or the full Big 3. The full birth card also gives you the house each placement falls in, your aspects, and a free reading written from your whole chart.