Emotional fit
Moon signs reveal how each person seeks safety and care.
Zodiac and birth-date compatibility
Two people. One living dynamic.
Compare two signs for a quick conversation starter, or use two birthdays for a calculated Sun, Mercury, Venus, and Mars comparison.
sign-level pattern
Your connection
A lively, evolving match.
There is plenty to learn from the way these two signs see the world.
Compare both birth datesCalculated comparison
Compare two birthdays across four relationship planets.
This date-level view calculates each person’s Sun, Mercury, Venus, and Mars signs. It names patterns to discuss; it does not rank people or promise an outcome.
Birth times are not required for this sign-level comparison. A complete synastry reading adds Moon signs, Rising signs, houses, and exact inter-chart aspects when both recorded times are available.
Enter two birth dates
These dates are used for this calculation only and are not saved.
A better way to compare
Compatibility is more than elements.
Sun signs offer a useful first look. A full relationship reading also considers Moon, Venus, Mars, Mercury, Rising signs, houses, and inter-chart aspects.
Affection style
Venus describes attraction, pleasure, and what feels valued.
Communication
Mercury shows how each mind processes and shares meaning.
The direct answer
What does astrology compatibility compare?
Astrology compatibility compares how two people’s chart patterns meet. A Sun-sign match describes only the broad identity layer; birth-date compatibility adds Mercury, Venus, and Mars; complete synastry compares both full natal charts by degree, house, angle, and aspect.
No responsible calculator can prove that two people are destined, incompatible, or guaranteed to stay together. The useful question is which needs, languages, attractions, and pressure points deserve clearer conversation.
How to use this tool
- 01
Start broad
Choose two zodiac signs for a quick element-and-modality conversation starter.
- 02
Add both birth dates
Calculate the Sun, Mercury, Venus, and Mars sign pattern for each person.
- 03
Keep the limits visible
Use exact birth times and places for Moon certainty, Ascendants, houses, and complete synastry.
Compatibility layers
Which comparison answers which question?
| Method | Uses | Can illuminate | Cannot establish |
|---|---|---|---|
| Sun-sign match | Two selected zodiac signs | Broad temperament, element, and modality | Emotional fit or long-term outcome |
| Birth-date comparison | Two dates; Sun, Mercury, Venus, Mars | Identity, communication, affection, and pursuit styles | Exact Moon, Rising signs, houses, or aspects |
| Full synastry | Two complete charts with accurate times and places | Inter-chart aspects, angles, houses, timing, and repeated themes | Consent, values, behavior, or a guaranteed future |
The four-planet lens
Look for the conversation between needs—not a percentage.
Two charts can contain both ease and friction. A strong comparison names the difference, shows where each person may be speaking a different symbolic language, and leaves room for lived experience to confirm or contradict the pattern.
Identity, vitality, and what each person is trying to author.
How each person processes, explains, questions, and repairs misunderstanding.
Affection, pleasure, attraction, and the values that make closeness worthwhile.
Pursuit, desire, initiative, conflict, and boundary-setting.
Questions, answered
Zodiac compatibility FAQ
How does the zodiac compatibility calculator work?
The quick mode compares two Sun signs as an introduction. The birth-date mode calculates each person’s Sun, Mercury, Venus, and Mars signs, then explains shared and contrasting patterns without turning the relationship into a score.
Is birth-date compatibility the same as synastry?
No. Birth-date compatibility is a useful sign-level comparison. Full synastry compares two complete natal charts, including exact degrees, Moon signs, Ascendants, houses, angles, and inter-chart aspects.
Do compatible zodiac signs guarantee a good relationship?
No. Astrology cannot guarantee a relationship outcome. Communication, consent, shared values, circumstances, and choices matter. Sign compatibility is best used as a prompt for discussion.
Which planets matter most for relationship compatibility?
The Sun and Moon describe identity and emotional needs; Mercury describes communication; Venus describes affection and values; Mars describes pursuit and conflict. Saturn, the angles, houses, and exact aspects add important context in full synastry.
Do I need both birth times?
Not for the four-planet birth-date comparison. Accurate birth times are needed for each Ascendant, houses, angles, and time-sensitive Moon placement in a complete synastry reading.
Are the birth dates stored?
The public compatibility tool sends the dates for the calculation and does not save them as a profile or report.
Go beyond sun signs