Birth Date Compatibility Calculator

Birth Date Compatibility Calculator: What It Really Shows

Identify two Sun signs from birthdays and compare traditional zodiac elements without a synastry score. Enter two dates to map them to conventional tropical zodiac Sun signs, then read about the associated elemental themes. The only thing taken from each date is the Sun sign; the time and place of birth play no part.

How to Use This Free Tool

Start with two calendar dates. Dates are mapped to tropical zodiac signs; this free result makes no claims about a full birth chart or planetary compatibility. The sign is found from the Sun’s approximate position at noon (UTC) on each date, so entering the same two dates again always returns the same pair of signs.

Identifying Sun signs

A calendar birthday can be mapped to a conventional tropical zodiac sign, with caution near sign transitions. On the first or last day of a sign the Sun may in fact have been in the neighboring one at the hour you were born; an astrologer would need the birth time to say.

Different scope from synastry

A date-only result is not an analysis of natal aspects or an individual relationship report. It compares two labels, each shared by roughly one person in twelve, and cannot distinguish you from everyone else born in the same month.

What the Free Result Does Not Include

Two dates are sufficient to identify approximate tropical Sun signs in this tool. They are not enough to reconstruct individual planetary contacts, Ascendant, house placements or other elements of a purchased full report.

Putting the result into context

Use the result as you would any shared trivia: a way to begin talking. The elemental themes describe a tradition’s picture of fire, earth, air and water, and the fair question is whether either of you recognizes yourself in it.

If the two signs come out in a relationship the tradition calls tense, nothing follows from that for a real couple. If they come out harmonious, nothing follows either. What two people build is not written in their birthdays.