astrology · Sun, Moon, Rising, Mercury, Venus, Mars
Big Six Astrology Calculator
See six personal placements in one compact result: identity, emotional needs, first impression, communication, relating and action. Exact degrees keep boundary dates honest; Rising uses time and birthplace coordinates.
free · local calculation · no account
Enter birth details
What the Big Six adds
Core
Sun, Moon and Rising describe three different layers: direction, inner regulation and the doorway through which experience arrives.
Voice and bond
Mercury adds the movement of thought; Venus adds value, attraction and reciprocity.
Action
Mars shows how desire gains traction, how challenge is met and where energy needs a clean outlet.
Six placements still cannot summarise a whole person. Use the result as a compact index into the complete chart, never as a diagnosis or verdict.
How the Big Six calculator works
The tool converts your local birth time to UTC using the offset you enter, then asks the Astronomy Engine ephemeris where the Sun, Moon, Mercury, Venus and Mars stood, as seen from Earth, in the tropical zodiac. Each longitude is split into a sign and an exact degree and minute, which is why someone born on a cusp day gets a real answer instead of a guess.
The Rising sign is different: it is not a planet but the degree of the zodiac crossing the eastern horizon at your birthplace. The script finds it from the exact UTC moment plus your latitude and longitude, which is why the coordinates are required and why a wrong time zone shifts it more than anything else.
How to read your result
- Start with the triad. Sun, Moon and Rising answer three separate questions: where am I heading, what do I need to feel settled, and how do I walk into a room.
- Then add the personal planets. Mercury colours how you think and talk, Venus what you value and find attractive, Mars how you push for what you want.
- Look for repeats. Three or more placements in one sign or element give that quality extra weight; a lone placement in a very different element often feels like the part of you others do not expect.
- Check the degrees. A placement at 0° or 29° sits right at a sign boundary; read both neighbouring signs and see which fits.
A worked example
Take a birth on 3 November 1993 at 19:15 in London (UTC+0). The calculator returns Sun in Scorpio 11°, Moon in Gemini 29°, Rising in Cancer 4°, Mercury in Scorpio 16°, Venus in Libra 23° and Mars in Scorpio 26°.
Read it as a story: three Scorpio placements (Sun, Mercury, Mars) suggest intensity, focus and a mind that digs. The Gemini Moon at 29° wants talk and variety to feel calm, and sits a breath from Cancer, so the emotional style may feel half curious, half protective. Cancer Rising softens the first impression: people meet warmth before they meet the depth. Venus in Libra adds a taste for fairness and beauty in relationships. For houses and aspects, open the same data in the full birth chart, and read single placements in more depth on Moon sign or Venus sign.
Limits worth knowing
The Moon moves roughly half a degree an hour and the Rising sign changes on average every two hours, so an approximate birth time can change both; in the example above, a birth around an hour later would already put the Moon in Cancer. The Sun, Mercury, Venus and Mars rarely change within a day. Historical summer time is the most common source of error, so check the offset that applied on that date. And six placements are a summary, not a verdict: they leave out houses, aspects and the outer planets.
Frequently asked questions
Is the result calculated from a real ephemeris?
Yes. Planetary longitudes and angles use the vendored Astronomy Engine ephemeris in the tropical zodiac.
Is this a scientific personality test?
No. The position is astronomical; the personal interpretation is an astrological tradition offered for reflection.
What if I don't know my birth time?
Use noon and treat the Rising sign as unknown. The Sun, Mercury, Venus and Mars will almost always be right; the Moon may be off if it changed sign that day, so check the degree.
Why does my Big Six differ from another app?
Usually because of a different time zone, summer time or birthplace, and occasionally because the other app uses a sidereal zodiac. This calculator uses the tropical zodiac.
Which of the six placements matters most?
Astrologers traditionally start with the Sun, Moon and Rising as the core triad. In practice, the one that sounds most like you is a good place to begin reading.