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Relationship Calculator

Figure out how you're related to your relatives. Calculate cousin relationships, removed degrees, and more.

Calculate Your Relationship
Select how many generations each person is from your common ancestor

Understanding Family Relationships

What is a "Common Ancestor"?

A common ancestor is the person from whom you're both descended. For example, if you share the same grandparents, those grandparents are your common ancestors.

How do cousin numbers work?

First cousins share grandparents. Second cousins share great-grandparents. The cousin number equals the number of generations back to your common ancestor, minus one.

What does "removed" mean?

"Removed" refers to a generational difference. Your first cousin's child is your "first cousin once removed" because there's one generation of difference between you.

Quick Reference

  • First Cousin: Your parent's sibling's child
  • Second Cousin: Your parent's first cousin's child
  • First Cousin Once Removed: Your first cousin's child OR your parent's first cousin

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Tree Family automatically calculates relationships as you build your tree. See how everyone connects at a glance.

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