Cousin chart
Pick the most recent ancestor you share with someone. Find what that ancestor is to you across the top, what it is to them down the side, and read the cell. Tap any cell to see the tree.
| To them ↓ · to you → | The ancestor | Parent | Grandparent | Great-grandparent | Great-great-grandparent | 3rd great-grandparent | 4th great-grandparent |
|---|---|---|---|---|---|---|---|
| The ancestor | — | ||||||
| Parent | |||||||
| Grandparent | |||||||
| Great-grandparent | |||||||
| Great-great-grandparent | |||||||
| 3rd great-grandparent | |||||||
| 4th great-grandparent |
Second cousin once removed
The shared ancestor is your great-grandparent and their great-great-grandparent. Expected shared DNA: 1.56%.
Open in the calculatorThe three rules behind every cell
- Same row and column number (the diagonal): same generation. Two steps down each is first cousins, three is second cousins, four is third cousins.
- Off the diagonal: the cousin number comes from the smaller of the two counts, and each step between them adds one "removed".
- Row or column of 1: one of you is the ancestor's child, so the relationship is sibling, aunt/uncle or niece/nephew, with "great-" added for each extra generation.
The chart is symmetrical: swap the row and column and you get the same cousin term, because a first cousin once removed is that to each other. Only the direct-line and aunt/niece cells flip (grandparent ↔ grandchild).
Charts like this were printed in 19th-century genealogy guides and are still how organisations such as the National Genealogical Society explain cousin terms. The grid here goes out to fifth cousins; past that, relationships follow exactly the same pattern.
Questions people ask
How do you read a cousin chart?
Find your relationship to the shared ancestor along the top row and the other person's relationship to that same ancestor down the side. The cell where the row and column meet is your relationship.
What is the difference between a cousin chart and a family tree chart?
A family tree chart records your actual relatives. A cousin chart (or relationship chart) is a lookup table that names the relationship between any two people once you know their common ancestor.
Can I print the cousin chart?
Yes. Use your browser's print command; the page prints the grid on its own without the navigation.