A second cousin usually shares about 3.1% of DNA with you, though the typical range is roughly 1.1% to 6.3%.

Simple meaning

That’s because second cousins usually share a great-grandparent , not a grandparent.

Quick comparison

  • First cousins: about 12.5% DNA shared.
  • Second cousins: about 3.1% DNA shared.
  • Second cousins once removed: about 1.6% DNA shared.

Important note

DNA sharing can vary a lot, so two second cousins may share more or less than the average and still be correctly related.

Relationship| Average DNA shared| Typical range
---|---|---
Second cousin| 3.4% 1| 1.1%–6.3% 1

Would you like me to also explain how a second cousin fits into a family tree?