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The attraction aspects
Venus and Mars between two charts are the chemistry. A close Venus–Mars contact is the spark; whether it lasts depends on what Saturn is doing nearby.
Premium report · Two charts
Synastrytwo charts, laid over one another.
Synastry compares two birth charts to find the aspects between them — the trines that explain the ease, the squares that explain the friction. Luxtra computes both charts and scores the connection: a Venus trine Mars between two people, for instance, is the classic signature of attraction that lasts.
The free tool · two birthdays · 30 seconds
Your compatibility score.
Your compatibility score
Enter your details above and tap compute — your result appears here, free.
The full reading · Premium
Every aspect between you · the full relationship reading
Join the waitlistYour computation travels into the app — no re-entry.The reel
See what your report
reveals.
A fifteen-second read of your report — the cover art set in motion, with one line of your reading spoken over it. Built on the same engine as the daily-zodiac reels.
- ✦ Per-language voice-over, music, and animated watermark
- ✦ 9:16 and 16:9 — made for Stories and the feed
- ✦ Shows the hero still until your reel renders
The space between two charts has its own weather. Where your planets meet theirs, something is decided — the laughter, the silence, the pull you cannot explain. Luxtra lays your chart over theirs and scores every thread between you. Some connections are written in the angles.
What it reveals
The substance of your reading.
What the overlay reveals — each thread computed between the two charts.
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The longevity aspects
Saturn contacts are the glue and the test. Saturn on a partner’s personal planet binds two people — sometimes as commitment, sometimes as weight.
III
The emotional fit
Moon-to-Moon and Moon-to-Sun contacts show whether you feel at home with each other — the difference between a great romance and a great roommate.
From a sample reading
Your Venus △ their Mars
This is the aspect the love songs are about. Your Venus, the way you give affection, falls into an easy trine with their Mars, the way they pursue — which means the wanting flows in both directions without anyone having to perform. Enjoy it. But read the Saturn contacts before you mistake ease for permanence.
Luxtra · Synastry · written for both charts
How Luxtra makes it
Computed by the sky, written by the machine.
Real astronomy first
Every figure is computed with the Swiss Ephemeris from your exact birth moment — the same engine astronomers use. Nothing here is approximated or invented.
Read by a reasoning model
AI interprets the computed chart against the full literature of astrology, in your language, remembering everything it has already read about you.
Paid for in Stars
Long-form reports run on Stars, one balance for chat, voice, readings, and art. Plans top you up monthly from $5.99; allowance Stars renew, purchased Stars never expire.
Frequently asked
Synastry, in plain answers.
What is a synastry chart?
Synastry is the branch of astrology that compares two birth charts to understand a relationship. It looks at the aspects each person’s planets make to the other’s — the contacts that create attraction, comfort, friction, and commitment.
What is a good compatibility score?
There is no single number in traditional astrology; compatibility is a pattern of aspects, not a percentage. Luxtra computes a weighted score from the strongest contacts as a quick read, then shows you the actual aspects behind it so you can see why.
Do we both need exact birth times?
For the most accurate synastry, yes — the Moon and the angles need the time. Without it, Luxtra still compares the planets it can place confidently and flags what depends on the missing minutes.
Your map · Free
Test your compatibility score
— free, from your chart.
The computed map is free. The reading that comes with it — what each line would do to your life — is written for your chart in the app.
Free to begin · no app needed to compute · reading from $5.99/mo