Moon sign calculator

About your Moon sign

What is a Moon sign?

Your Moon sign is the zodiac sign the Moon was in when you were born. The Moon is your emotional nature and what makes you feel safe.

How is it different from my Sun sign?

The Sun spends about a month in each sign, so your birthday alone tells your Sun sign. The Moon spends two to two and a half days in each sign, so a birth time makes your Moon sign certain. Two people born a few days apart can share a Sun sign and have different Moon signs.

Do I need my birth time?

Not always. Your birth date is enough when the Moon stayed in one sign all that day. On a little under half of all days it changes sign at some point, and then your birth time decides which sign is yours. Without a time we show both signs it may have been in, and which one the wheel shows.

Why does my birthplace matter?

Your birthplace sets the time zone of your birth date. With no place, your birth date could fall anywhere in about two days of the world's clocks, so we often show two signs. Add your town or city to narrow it to your own birth day.

How is it calculated?

Planet positions come from the Swiss Ephemeris, through the open-source Kerykeion library. The zodiac is tropical. Without a birth time, the chart is drawn for noon on your birth date, or for 12:00 UTC when there is no birthplace either. More about how we calculate →