About this calculator
Your Sun sign is what you get when someone asks "what's your sign?", but astrologers rarely stop there. The "Big Three" are the three most personal points in a birth chart: the Sun, which describes your core identity and direction; the Moon, which describes your emotional needs and the private you; and the Rising sign, or Ascendant, which describes the first impression you make and the style you meet the world with. Two people with the same Sun sign can feel completely different because their Moon and Rising differ.
Enter your birth date, birth time and the city you were born in. The calculator converts your local birth time to Universal Time using the historical time zone and daylight saving rules for that city, then computes the real positions of the Sun and Moon along the zodiac and the degree of the zodiac rising on the eastern horizon at that moment. It is the same geometry a professional chart uses, simplified to the precision needed to identify your signs.
Your birth time matters most for the Rising sign, which changes roughly every two hours. The Moon moves through a sign in about two and a quarter days, so most people get a clear Moon sign even without a time. If you do not know your time, leave it blank: you will still get your Sun and Moon, and we will tell you if your Moon changed signs on your birthday. Not born in one of the listed cities? Choose the nearest large city in the same time zone.
How it works
- Enter your date of birth and, if you know it, your exact time of birth (check a birth certificate if you can).
- Choose your birth city or the nearest big city in the same time zone.
- Read what your Sun, Moon and Rising signs say about you, then compare with friends.
FAQ
What are the Big Three in astrology?
They are your Sun sign (core self), Moon sign (emotions and inner needs) and Rising sign or Ascendant (outer personality and first impressions). Together they give a much fuller picture than the Sun sign alone.
Why do I need my birth time and city?
The Rising sign depends on which part of the zodiac was on the eastern horizon at the moment you were born, which changes about every two hours and depends on your location. The Moon also moves about half a degree per hour, so your time can matter on days it changes signs.
How accurate is this calculator?
The astronomy is accurate to within a few arcminutes, which is much finer than a sign boundary, and we spot-checked it against well-known published charts. The biggest source of error is the birth time itself: if it is rounded or estimated, your Rising sign could be off, especially near the edge of a sign.
What if I do not know my birth time?
Leave the time empty. You will get your Sun and Moon signs calculated for noon, plus a warning if the Moon changed signs during your birthday. The Rising sign cannot be determined without a time.
Is my birth data stored anywhere?
No. Everything is calculated in your browser and nothing is sent to a server. The form may remember your entries on your own device so you do not have to retype them.
For entertainment and self-reflection only. Astrology is not a science, and this calculator is not a psychological assessment or a substitute for professional advice.