Big 3 calculator
Your Sun, your Moon, and your rising sign: the short version of your whole chart, computed precisely from your birth details. The Sun is your core, the Moon is your inner life, the rising is the door you meet the world through. No account required.
How to read your big 3
Read them as one voice in three registers, never as a list. Your rising sign is how you arrive: the first impression, the instinctive style, the room's first read of you. Your Sun is what you are becoming: the core project of the life, the thing that feels like purpose when you are doing it. Your Moon is what you need underneath both: how you feel, what restores you, what home means to your body.
Most people recognize their rising sign before anything else, because it is the version of them the world already knows. The Sun tends to be something you grow into across a whole life. The Moon is the one only your closest people could describe. When the three sit in very different signs, that is not a contradiction: it is dimension. The chart is a house with many rooms, and these are the first three doors.
One honest note: your rising sign needs an accurate birth time, because the Ascendant changes sign about every two hours. Without a time you still get your Sun and Moon truthfully computed, and we will say so plainly rather than guess.
The big 3 are the doorway. The chart is the house.
The Twelve Rooms writes deep natal readings from this exact math: every planet, all twelve houses, one cohesive reading. I read every line myself.
Explore the readingsCommon questions
What is your big 3?
Your Sun sign, Moon sign, and rising sign (the Ascendant). Together they are the short version of your natal chart: the core, the inner life, and the way you meet the world.
Do I need my birth time?
For the Sun, no. For the rising sign, yes: it changes about every two hours. The Moon usually holds one sign all day, but on some days she changes signs partway through, so a time makes her certain too. Your birth certificate usually has the time.
Why is my rising sign different from other sites?
If a birth time is off by even a few minutes near a sign change, the rising sign can differ. We compute from the Swiss Ephemeris with your exact time, place, and timezone, so a mismatch usually traces back to the time entered elsewhere.
How is this calculated?
Swiss Ephemeris, whole-sign houses, exact coordinates and timezone from your birthplace.