Moon Sign
Calculate your Moon sign. See what the time changes.
Choose your birth date and city. With a birth time, calculate your Moon sign and degree. Without one, see whether the Moon changed signs during that local day, then learn how a sign differs from a phase.
Free and in-page, with no account. This calculator does not save your details.
Calculate your Moon sign here.
Choose your birth date and city. With a birth time, see your Moon's degree; without one, find out whether it changed signs that day. No account needed.
At a glance
The fastest body in the sky.
Where the Moon stood at birth
Your Moon sign is the sign the Moon occupied at the moment you were born. Where the Sun sign is read as what you want, tradition asks the Moon what you need and what makes you feel safe.
Thirteen degrees a day
The Moon covers about 13.2 degrees of zodiac a day and changes sign roughly every two and a half days. It is the fastest body in the sky, which is why a Moon sign turns over far more often than a Sun sign.
Some dates need the clock
If you were born on a day the Moon changed sign, your birth time decides which side of the crossing you are on. On other days the date alone settles it — the question is only which kind of day yours was.
Sign, not phase
A Moon sign and a Moon phase are different things. The phase says how much of the Moon is lit; the sign says where it stands in the zodiac. Being born on a full moon tells you nothing about your Moon sign.
What the Moon sign actually is
A birth chart is a map of how the sky looked from one place at one moment. The Sun was in some sign at that instant, the Moon in another, each planet in another still. Your Moon sign is the second line of that list: the sign the Moon occupied at the minute you were born.
It is easy to see why the Sun sign became the famous one. The Sun stays in a sign for about a month, so a birth date is enough to pin it down and it fits in a newspaper column. The Moon is far quicker. It travels the whole zodiac in roughly 27.3 days, which works out to about 13.2 degrees a day. Since a sign is thirty degrees, the Moon spends an average of two and a half days in each one.
That difference in speed is why two people born on the same day can share a Sun sign and not a Moon sign. Two siblings born two days apart often share a Sun sign, while their Moon signs may differ. A Moon-sign description can feel more personal, but it is not a personality measurement. One chart placement cannot describe a whole person.
Why the date is sometimes not enough
Because the Moon changes sign every two and a half days, a substantial share of dates on the calendar are crossing days. On those days the Moon is in one sign in the morning and the next by evening. If you were born on such a day, your birth time is the thing that decides your Moon sign; without it the answer splits in two.
This differs from the rising sign. The Ascendant depends on the birth moment and place, and its rate is not fixed. Baby Astro does not show it when the time is unknown. The Moon moves more slowly, but an unknown-time Moon reading should not be treated as exact either.
The calculator on this page compares the start and end of your birth date in the selected city's local time. If the Moon stayed in one sign it shows that sign without an exact degree; if it changed signs, it shows both candidates. The full birth-chart screen does not present an unknown-time Moon as an exact placement.
Moon sign and moon phase are not the same
These two get confused constantly, because both are called "the Moon" and both depend on the moment you were born. They answer different questions.
A moon phase is about the angle between the Sun and the Moon: how much of the Moon's face looks lit from here. New moon, first quarter, full moon, last quarter — those are phases, and they repeat on a cycle of about 29.5 days. A Moon sign is about which thirty-degree slice of the zodiac the Moon occupies, on a cycle of 27.3 days.
Because the two cycles have different lengths, they drift independently. Being born near a full moon does not tell you your Moon sign, and having the Moon in Taurus does not tell you the phase at birth. The Moon's zodiac position is the same for everyone at one instant; a person's result depends on when they were born.
What tradition reads into the Moon
In classical astrology the Moon is the inward-facing body. Where the Sun stands for what faces outward — will, direction, the thing a person is trying to become — the Moon stands for habit, need and reflex. How you settle yourself when nobody is watching, what you reach for when you are tired, which surroundings actually rest you.
Some readers find Moon-sign descriptions closer to their experience than Sun-sign descriptions. Tradition uses the two placements for different questions: outward direction and inward need. Different descriptions need not signal a contradiction or a problem. What you actually do tells more about you than a chart does.
Even so, this is a description and not a diagnosis. Astrology does not measure anyone's emotional makeup, and a Moon sign does not sentence anyone to a temperament. What it offers is a vocabulary for naming something you probably already knew about yourself. If the words fit, they have done their job. If they do not, it is the description that is wrong, not you.
How we compute it
A Moon sign is not looked up in a table. Baby Astro computes the Moon's ecliptic longitude for your birth moment from an ephemeris, then asks which thirty-degree slice that longitude falls in. The same calculation serves the Sun, the planets and the nodes — the Moon sign is not a separate method, it comes from the same place as the rest of the chart.
If your birth time is known, the web calculator converts it to UTC with the historical offset when the browser supports that data. Otherwise it uses an approximate longitude-based offset. That difference may affect a Moon position near a sign boundary.
If your birth time is unknown, this page compares 00:00 and 23:59 in your selected city's local day. It gives a sign-level answer if the Moon stayed in one sign, or both possibilities if it crossed a boundary. An exact degree is shown only with a known birth time.
Frequently asked questions
Find your Moon sign here.
Enter your birth date and city. See the degree if you know the time, or learn whether two signs are possible that day.
Find my Moon signKeep your chart with you on Android.
