Astrology
Calculate your match: Sun, Mercury, Venus and Mars of two birthdays
Enter two birth dates. The calculator places the Sun, Mercury, Venus and Mars of each person in a sign and shows how the signs of each pair relate: same sign, neighbours, sextile, square, trine or opposition.
It gives no score and no verdict. Each result is a reading aid: what the pair of planets stands for, and how their signs sit toward each other.
How this is calculated
Positions are calculated in your browser with the Astronomy Engine library, for 12:00 UT on each date, in the tropical zodiac. Nothing is sent to our server and nothing is stored.
The Moon is left out on purpose. It travels 12 to 15 degrees a day, so without the time and place of birth its sign can be wrong. Mercury, Venus and Mars can also change sign on the day itself; planets within one degree of a boundary are marked with an asterisk.
Signs are compared as whole signs, the way Ptolemy did. A pair of signs is an aspect only at 0°, 60°, 90°, 120° or 180°; signs 30° or 150° apart do not see each other. The full synastry, with time and place, is not part of this calculator.
Astrology is a tradition of interpretation, not a scientific predictor of relationships. Treat the results as something to think about, not as advice.