First cousin once removed vs. second cousin — what's the difference?
They're different. A second cousin is in your own generation — you share a great-grandparent. A first cousin once removed is a generation apart — your first cousin's child or your parent's first cousin. Same-generation means 'not removed'; a generation gap means 'removed'.
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FAQs
Quick rule to tell them apart?+
Same generation as you → second cousin. A generation up or down from a first cousin → first cousin once removed.
Does the calculator store my family details?+
No — it runs entirely in your browser. Nothing you enter is uploaded or saved on our servers.
Start with one relative and see what comes back.
Add what you remember and AncestorIQ searches for the rest. Free to build your tree for as long as you like.
No credit card needed. Your tree stays yours.
