Moon sign calculator

The Moon is the fastest-moving body in the sky: it crosses a full sign in about two and a half days. That means your birth date alone is usually enough to find your Moon sign; a birth time is only needed on the days when the Moon changes sign on the day you were born.

If you don't know your birth time

If you leave the time field blank, the calculator checks which sign the Moon was in from the start to the end of your birth day. If the Moon stayed in a single sign all day, the result is certain. If it changed sign during the day, the calculator gives you the exact time of the change; if you know whether you were born before or after that time, your Moon sign is settled.

The Moon's phase

The calculator also shows what percentage of the Moon was illuminated at the moment you were born, and whether it was waxing or waning. Both values are calculated from the angle between the Sun and the Moon. If you don't enter a time, the calculation uses noon; the illuminated percentage can change by up to twelve percent over the course of a day.

What does the Moon sign describe?

In astrological tradition, the Sun is associated with conscious direction, while the Moon is associated with emotional needs, habits and how a person feels secure. Daily horoscopes only look at the Sun sign; the Moon sign is usually left out entirely.

These are astrology's interpretive framework, not scientifically validated psychological measurements.

How is it calculated?

• The Moon's position is calculated with Swiss Ephemeris.
• The birth day is scanned from midnight to midnight according to the birth place's time zone on that date (including daylight saving).
• The moment of the sign change is rounded to the minute; the last minute of each table row still belongs to that sign.