What your Mercury sign says
Mercury is the planet astrologers associate with the mind: thinking, learning, speaking, writing, trading and getting around. Where your Sun sign describes who you are, your Mercury sign describes how you take in the world and put it into words. Two people with the same Sun sign can think and talk very differently because their Mercury signs differ, which is why it comes up in study, in work and in every question about how you communicate.
| Mercury sign | How astrologers describe the mind |
|---|---|
| Aries | Quick, direct, decides fast |
| Taurus | Steady, practical, slow to change its views |
| Gemini | Curious, witty, follows several ideas at once |
| Cancer | Intuitive, remembers how things felt |
| Leo | Confident, dramatic, a storyteller |
| Virgo | Precise, analytical, notices every detail |
| Libra | Diplomatic, weighs every side |
| Scorpio | Probing, strategic, keeps its own counsel |
| Sagittarius | Broad, frank, drawn to big ideas |
| Capricorn | Structured, realistic, plans ahead |
| Aquarius | Original, independent, looks to the future |
| Pisces | Imaginative, intuitive, thinks in images |
In traditional astrology Mercury rules Gemini and Virgo, the signs where it is said to work most naturally, and it is exalted in Virgo as well. The calculator gives the full reading for your sign, its element and mode and, with a birth time, its house: Mercury in the 3rd house turns the mind to talk, writing and your everyday surroundings; in the 9th, to study, travel and the big questions.
Why your Mercury sign is close to your Sun sign
Mercury orbits close to the Sun, so from Earth it never strays more than about 28° from it. That keeps your Mercury sign within one sign of your Sun sign: the same sign on about half of all birthdays, and the sign before or the sign after on about a quarter each. A Sun in Leo, say, comes with Mercury in Cancer, Leo or Virgo.
Mercury also moves fast. It usually spends two to three weeks in a sign, but around a retrograde it can stay in one sign for up to about ten weeks, and it sometimes slips back into the sign it has just left. The results give the exact dates Mercury entered and left your sign in your own time zone, and a table of every Mercury sign in your birth year, with any sign it re-entered while retrograde marked.
Mercury retrograde at birth
Three or four times a year, Mercury appears to slow down, stop and move backward for about three weeks, and about one person in five is born during one of these loops. Astrologers read a retrograde Mercury in the birth chart not as a flaw but as a mind that turns inward: reflective, original, slower to speak and often better at revisiting and rethinking than at snap answers. The Mercury retrograde page has the dates of every loop, past and coming.
If you don't know your birth time
Without a birth time, the calculator checks Mercury's sign across the whole local birth day. If it changes, you get both possible readings and the approximate local change time. The degree, house and personal map links need a birth time; a sign-only share card is available when the sign is certain. Mercury return dates use noon as a reference and are marked approximate. You can print or save the result as a PDF.
Mercury and how you get along
Astrologers compare Mercury signs to see how two people talk and think together. Mercury signs in the same element are said to understand each other easily, and one person's Mercury touching the other's Sun, Moon or Mercury is read as a meeting of minds. The synastry chart lists every contact between two charts.
Your Mercury lines on the map
Mercury has four lines on your astrocartography map, showing where it was rising, setting, overhead and underfoot when you were born. Places near them are read as places for learning, writing, trade and conversation. Read about each one in the Mercury lines guide or see them on your free astrocartography chart.