Create Your Synastry Chart
Learn Astrology
Clarity. No Fluff.
Sun Conjunct Venus in Synastry: A Love So Natural, It Feels Fated
Explore the warmth and harmony when Sun meets Venus in synastry - an aspect that brings natural affection, admiration, and a sense of ease in relationships.
Venus Conjunct Mars in Synastry: Who Feels it More?
Explore the magnetic attraction and passionate dynamics when Venus meets Mars in synastry - one of the most potent aspects for romantic chemistry.
Moon Conjunct Mars in Synastry: How the Signs Shape the Connection
Discover the emotional intensity and instinctive connection when Moon meets Mars in synastry - a powerful aspect that ignites deep feelings and protective instincts.
Accurate.Simple.Capable.
Made for All Levels
The chart wheel reads cleanly without astrological background. Aspect grids and planetary conditions are one click deeper for those who want them.
Simple Surface, Deep Core
Every chart type — natal, transit, synastry, returns, progressions — from a single profile.
Swiss Ephemeris
Swiss Ephemeris under professional license. Accurate to the minute of arc.
House Systems & Orbs
Switch between Placidus, Whole Sign, Koch, Equal House, and several others. Tighten or loosen aspect orbs. Add asteroids. Defaults work; the controls are there if you want them.
Accurate.
Simple.
Capable.
Made for All Levels
The chart wheel reads cleanly without astrological background. Aspect grids and planetary conditions are one click deeper for those who want them.
House Systems & Orbs
Switch between Placidus, Whole Sign, Koch, Equal House, and several others. Tighten or loosen aspect orbs. Add asteroids. Defaults work; the controls are there if you want them.
Simple Surface, Deep Core
Every chart type — natal, transit, synastry, returns, progressions — from a single profile.
Swiss Ephemeris
Swiss Ephemeris under professional license. Accurate to the minute of arc.
A Couple
of Things
What is a synastry chart?
A synastry chart compares two birth charts by mapping the aspects each person's planets make to the other's. Where Mars touches Venus, where Saturn squares the Moon — these inter-aspects describe how two people meet, where they reinforce each other, and where the friction is.
How accurate is synastry for relationship compatibility?
Calculations use Swiss Ephemeris and are accurate to the minute of arc. Synastry describes the astrological pattern between two charts — it doesn't predict whether a relationship works. People are not their charts.
Do both people need exact birth times for synastry?
Exact birth times give you the full picture — house overlays (whose Mars falls in whose 7th, etc.) and aspects to the angles. Without them, planet-to-planet aspects still calculate correctly, but the house and angle layer isn't reliable.
How does synastry work on this site?
Each planet on either chart is clickable. Selecting a planet shows every cross-chart aspect it makes — the planets it touches, the type of aspect, and the orb.
Is the synastry chart calculator free?
Yes. Generate unlimited synastry charts without signing up. Sign up only if you want to save your profile and access it faster next time.
Is my relationship data private?
Yes. Birth data for both people is stored securely and never shared. You can delete any saved profiles anytime.