Create your link. Let the other person complete the picture.
Compare two birth charts through exact degrees, inter-chart aspects, house overlays, and repeated contacts. Chemistry Deck turns that technical comparison into a concise story about attraction, ease, friction, impact, and growth—without calling anyone a red flag.
Enter only your own birth details.
Send one private link. The other person adds their chart.
Six focused sections reveal the shared pattern.
A result designed to be read, not decoded
The same precise synastry signals behind Regu’s technical tools are condensed into one deliberate sequence. One section is shown at a time, with the evidence still available underneath.
A birth chart compatibility comparison built from two complete charts
Chemistry Deck calculates both natal charts from birth date, time, and city, then reads exact planetary positions, inter-chart aspects, house overlays, and repeated contacts. Each aspect is weighted by orb, so a tighter contact contributes more than one near its allowed limit.
How this differs from Sun-sign compatibility
Sun-sign matching compares one placement with another. This comparison also considers the Moon, personal planets, angles, Nodes, Vertex, Lilith, and directional house activations where the birth data supports them. If a birth time is unknown, time-sensitive houses and angles are treated with lower confidence rather than presented as exact.
What a Chemistry Deck score does—and does not—mean
Scores separate attraction, emotional ease, stability, recognition, and growth instead of forcing one verdict. A high score describes a strong pattern in that layer; it does not prove compatibility, predict duration, or decide whether a relationship is healthy.
Is this another compatibility calculator?
No. Chemistry Deck uses Regu’s existing synastry, relationship-pattern, and directional-impact engines, then turns them into a private two-person invite and a shareable six-part result.
Can the other person see my birth details?
No. The invite page reveals only your first name. Birth date, time, location, and coordinates are never returned by the public invite API or placed in the URL. The invitation stops accepting new entries after 7 days, and raw birth details are removed from the active invitation once the deck is created.
Does a high chemistry score mean we are a perfect match?
No. Chemistry is only one dimension. The deck keeps emotional ease, stability, growth, and directional impact separate.
Read the patterns behind the scores.
Use these guides when you want the fuller context behind warmth, attraction, recognition, stability, and uneven impact.
Browse all readings
Moon-Venus In Synastry
Read why warmth and emotional ease can be strong without defining the whole relationship.
Saturn In Synastry: Commitment Vs Weight
Separate durability and responsibility from emotional pressure before reading a stability score.
Why Some People Feel Like Home Immediately
Useful context for recognition, comfort, and the difference between familiarity and safety.
North Node Conjunct Venus
A closer look at attraction and growth when Venus and the Nodes become part of the repeated pattern.