Astrology Compatibility Calculator

Compare two complete birth charts—not just Sun signs—to explore connection, ease, friction, and growth points.

SYNASTRY · TWO BIRTH CHARTS

What the calculator compares

Synastry overlays two natal charts and measures aspects from one person's planets to the other person's planets. Moon–Venus may describe warmth, Mercury contacts communication, Mars contacts drive and chemistry, and Saturn contacts durability, responsibility, or pressure.

Sun-sign compatibility misses most of this information. A full comparison needs both birth dates, places, and preferably exact times.

How to use AskCelesta compatibility

  1. Create a free account so two charts can be stored.
  2. Save one natal chart for each person.
  3. Open Compatibility and select the charts.
  4. Explore the bi-wheel, aspect lists, readings, and share card.
Requirement: compatibility mode needs a free account and two saved charts. This prevents repeated data entry and makes the pairing shareable.

How to interpret the result

Trines and sextiles are often easier channels; squares and oppositions bring tension that requires awareness; conjunctions intensify the planets involved. No aspect is automatically good or bad. Ease can become passive, while well-handled friction can create honesty or growth.

Compatibility is not a score

Astrology cannot measure consent, communication skills, safety, or shared values. AskCelesta shows actual contacts rather than claiming a relationship is destined to succeed or fail. Use the chart to generate better questions, not override experience.

Ready to compare both complete charts?

Create charts to compare →Free account and two saved charts required

Frequently asked questions

What is synastry?

Synastry compares two natal charts and interprets aspects between their planets and angles.

Do both people need exact birth times?

Planet aspects remain useful, but the Moon, Ascendant, angles, and houses may be inaccurate without them.

Can astrology predict if a relationship will last?

No. A compatibility chart describes symbolic dynamics, not a guaranteed outcome.