Birth Card Compatibility Calculator
Quick answer
Enter two birthdays to see both birth cards, each person’s Moon-plus-13 Life Path constitution, where the other person’s birth card lands inside that spectrum, and which Life Path cards both people share.
The first layer is simple: two birth cards meeting. The deeper layer is the Life Spread. Each person carries a spectrum: Moon support, primary birth-card energy, Mercury mind, Venus love, Mars action, Jupiter growth, Saturn lesson, Uranus pivot, Neptune dream, Pluto shadow, Princess reward, Prince responsibility, Queen embodiment, and King command.
How to read the result
Start with the birth-card chemistry, then read the Life Path cross-reference. If the other person’s birth card lands in your Venus, Mars, Saturn, Neptune, or Pluto position, the relationship will feel very different than if it lands nowhere in the first Life Path spectrum. Shared Life Path cards show where both people are carrying the same card in different roles. For the broader method, read more about how Cardology compatibility works.
Frequently asked questions
Does same suit mean better compatibility?
No. Same suit can feel familiar, but it can also amplify the same blind spots.
What is a Life Path constitution?
It is the Moon support card plus the 13 Life Path cards starting from the birth card in the Life Spread. It shows the person's mental, love, action, growth, lesson, shadow, reward, responsibility, embodiment, and command lines.
Can Cardology decide whether a relationship should continue?
It can name the pattern with surprising clarity: where two people bond, where they trigger each other, and what each person tends to need. The actual decision still belongs to the people living it.
Should I compare ruling cards too?
Yes. Birth cards show the core pattern; ruling cards can show expression, attraction, and day-to-day style.
Related pages
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