Moon Sign Calculator: Find Yours by Date and Time

Your Moon sign is the zodiac sign the Moon was in at the moment you were born. Enter your birth date and place above and the calculator works out where the Moon was. If that settles it, you get one answer and a plain statement that it is certain. If the Moon changed sign that day, you get both signs and the clock time of the change, so you can see which side of it you were born on.

What is a Moon sign?

In astrology the Sun sign describes the self you show and the Moon sign describes the self you live in: your moods, your instincts, and what you need in order to feel safe. It is one of the three placements most people learn first, with the Sun sign and the rising sign.

The Sun takes a year to go round the zodiac, so everyone born in the same four weeks shares a Sun sign. The Moon goes round in about 27 days. Two people born a few days apart, with the same Sun sign, usually have different Moon signs, which is the usual explanation astrologers give for why two Leos can feel nothing alike. Our guide to Sun sign and Moon sign covers how the two are read together.

How do I find my Moon sign?

Use the calculator at the top of this page. It asks for three things, and only the first is required:

1. Birth date. Always needed.
2. Birth place. This sets the time zone, including any daylight saving time in force that day.
3. Birth time. Needed only when the Moon changed sign on your birth date.

Start with the date and the place. On more than half of all dates the Moon stays in one sign from midnight to midnight, and the calculator will tell you the answer is certain without a birth time. Add the time only if the result shows two signs. If you leave the place out, the calculator checks your date in every time zone on Earth, which nearly always spans a change, so it will usually ask for the place.

Why does the birth time matter?

The Moon is the fastest thing in a birth chart. It covers about 13 degrees of the zodiac a day, which is roughly one degree every two hours, and each sign is 30 degrees wide.

We measured how long it stays in a sign instead of quoting the usual "two and a half days". Across every Moon sign change from 1900 to 2100, which is 32,084 of them, the Moon spent an average of 2.28 days in a sign. The shortest stay was 46.9 hours and the longest was 61.1 hours. The stays vary because the Moon speeds up when it is nearest the Earth and slows down when it is farthest.

How often do I need a birth time?

Less than half the time. Counting the same 200 years day by day, the Moon changed sign on 43.9% of calendar dates. On the other 56.1% it stayed in one sign from midnight to midnight (in Universal Time). On a date like that, once the place is known, the birth time does not matter at all.

That figure is why a calculator that silently assumes noon is wrong so often. On a date with a change, a noon guess puts everyone born on the other side of the change in the wrong sign, and gives them no warning. This calculator does not assume a time. It shows you the change.

A worked example

Take someone born in London on 14 March 1992. On that day the Moon moved from Cancer into Leo at 7:20 pm. With the date and place alone, the calculator returns both signs:

• Cancer Moon if born before 7:20 pm
• Leo Moon if born at or after 7:20 pm

Add a birth time of 9:30 am and the answer is a Cancer Moon, at 24.1 degrees of Cancer. The calculator also reports the margin: that birth time would have to be wrong by almost ten hours to change the result, so a time remembered as "sometime in the morning" is good enough.

Someone born in London a day later, on 15 March 1992, needs no birth time. The Moon was in Leo for the whole day.

What if I do not know my birth time?

First check whether you need it. Enter your date and place. If you get one sign marked certain, the time makes no difference.

If you get two signs, these are the places a birth time is usually written down:

• Your birth certificate. In the United States the long-form certificate normally includes the time; the short form often leaves it out, so ask the state vital records office for the long form. In England and Wales a time is recorded only for twins and other multiple births. In Scotland it is recorded for every birth.
• Hospital or maternity records, a baby book, a birth announcement, or a hospital wristband kept by a parent.
• Family memory. "Before lunch" or "in the middle of the night" is often enough, because the calculator tells you the exact time of the change and you only need to know which side you were on.

If none of that settles it, read both Moon sign pages. Most people recognise one of the two straight away. Treat that as a working answer, not a proven one.

Why do Moon sign calculators disagree?

When two calculators give you different Moon signs, the cause is almost always one of these four.

A blank time filled in for you. Many tools take noon, or midnight, when the time field is empty and do not say so. On a date with a sign change that is a coin toss.

The wrong time zone. A birth time means nothing until it is tied to a place. Some tools read the time in the zone of the device you are using today. Others ignore daylight saving time, or apply today's rules to a year that had different ones. An error of one hour moves the Moon about half a degree, which is enough to matter near a change. This calculator uses the time zone history for the place you choose.

Tropical or sidereal zodiac. Western astrology uses the tropical zodiac, tied to the seasons. Vedic astrology uses the sidereal zodiac, tied to the stars, which currently sits about 24 degrees earlier. A sidereal calculator will put most people's Moon in the sign before their tropical one. Neither is a mistake; they are two systems. This page is tropical. Our Vedic astrology calculator gives the sidereal Moon and its nakshatra, and tropical vs sidereal explains the gap.

Where the Moon is measured from. The Moon is close enough that its position against the stars shifts by up to about one degree depending on where on Earth you stand. Astrology by long convention measures from the centre of the Earth, and so does this calculator. A tool that measures from the birth place can differ by up to roughly two hours' worth of Moon movement.

How accurate is this calculator?

The Moon's position comes from an astronomical ephemeris, the open-source Astronomy Engine library, which states an accuracy of within one arcminute against NASA's Jet Propulsion Laboratory data. The Moon takes about two minutes to cross one arcminute, so the times of sign changes shown here are good to within about two minutes.

Your recorded birth time is nearly always the larger uncertainty. Times written on certificates are commonly rounded to the nearest five minutes or more. That is why the result tells you how far out your birth time would have to be to change the answer. If that margin is a few hours, you can trust the sign. If it is a few minutes, treat the result as "on the boundary" and read both signs.

The calculation runs in your browser. Your birth date and time are not sent to us. The city search sends only the letters you type, to look up the time zone.

As a check on the method, the calculator puts the Moon at 7.9 degrees of Libra at 20:17 Universal Time on 20 July 1969, the minute Apollo 11 touched down on it. Our tests also confirm that the same code places the Sun in the right sign for every month of the year. The wider approach is described in sources and methodology.

What does each Moon sign mean?

These are the traditional associations, one line each. Follow a link for the full reading of that placement.

• Aries Moon: quick, hot feelings that pass as fast as they arrive.
• Taurus Moon: steady and grounded, comforted by routine and simple pleasures.
• Gemini Moon: feelings worked out by talking and thinking them through.
• Cancer Moon: deeply sensitive and protective; the Moon's own sign.
• Leo Moon: warm and expressive, with a need to be seen and appreciated.
• Virgo Moon: practical care, and calm found in order and being useful.
• Libra Moon: at ease in harmony and company, unsettled by conflict.
• Scorpio Moon: intense and private, with feelings that run deep.
• Sagittarius Moon: optimistic and restless, secure when there is room to roam.
• Capricorn Moon: composed and self-reliant, with feelings kept in hand.
• Aquarius Moon: independent, understanding feelings by standing back from them.
• Pisces Moon: compassionate and dreamy, absorbing the moods of a room.

How does the Moon sign fit with the Sun and rising signs?

Astrologers read the three together. The Sun sign is the core character, the Moon sign is the emotional life, and the rising sign, also called the ascendant, is the first impression. The rising sign changes about every two hours, so it always needs a birth time and place. You can see all three on one wheel with the birth chart calculator.

To compare your Moon with someone else's, use the Moon sign compatibility chart. To see which sign the Moon is in for everyone today, as opposed to at your birth, see Moon sign today.

Is a Moon sign scientifically real?

The position of the Moon is astronomy, and this page computes it to within a couple of minutes. What that position says about a person is astrology, a tradition of interpretation that controlled tests have not supported. We present it as an interest and belief framework and keep the two apart on purpose. Our article is astrology a science? goes through what has been tested.

FAQs

How do I find my Moon sign? Enter your birth date and place in the calculator on this page. If the Moon did not change sign that day, that is enough. If it did, add your birth time and the calculator will tell you which sign you were born under.

Can I find my Moon sign without a birth time? Often, yes. The Moon stays in one sign all day on 56.1% of dates, and on those dates the time does not matter. On the rest, the calculator shows both possible signs and the exact time of the change.

How long does the Moon stay in one sign? An average of 2.28 days, measured over every sign change from 1900 to 2100. The shortest stay in that period was 46.9 hours and the longest was 61.1 hours.

Why did another calculator give me a different Moon sign? Usually because it assumed a birth time, used the wrong time zone, or uses the sidereal zodiac of Vedic astrology, which sits about 24 degrees earlier than the tropical zodiac used here.

Is my Moon sign the same as my Sun sign? Only by coincidence, about one time in twelve. It happens when you were born near a new moon, when the Sun and Moon are in the same part of the sky.

Does the calculator store my birth details? No. The calculation runs in your browser. Your birth date and time stay on your device, where they are remembered so the other tools on this site are filled in for you.

About this tool

Built and maintained by the AstrologyBay Editorial Team. The Moon's position is computed astronomically, and the statistics on this page were measured with the same code over the years 1900 to 2100. What a Moon sign means is the reading the astrological tradition gives it.