One shared ancestor, two branches
Find your cousin relationship from a shared ancestor.
Choose how a shared ancestor is related to each person. See the cousin number, what “removed” means and the two branches that explain the result.
Grandparent through sixth-great-grandparent · Optional names and notes · Text download · Browser printing · No account
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Cousin relationship chart
Rows: the shared ancestor is person A’s… Columns: the same ancestor is person B’s… Find where the row and column meet.
Scroll sideways to see every generation, through sixth-great-grandparent. ↔
| Person A ↓ / Person B → | Grandparent | Great-grandparent | 2nd-great-grandparent | 3rd-great-grandparent | 4th-great-grandparent | 5th-great-grandparent | 6th-great-grandparent |
|---|---|---|---|---|---|---|---|
| Grandparent | 1C | 1C1R | 1C2R | 1C3R | 1C4R | 1C5R | 1C6R |
| Great-grandparent | 1C1R | 2C | 2C1R | 2C2R | 2C3R | 2C4R | 2C5R |
| 2nd-great-grandparent | 1C2R | 2C1R | 3C | 3C1R | 3C2R | 3C3R | 3C4R |
| 3rd-great-grandparent | 1C3R | 2C2R | 3C1R | 4C | 4C1R | 4C2R | 4C3R |
| 4th-great-grandparent | 1C4R | 2C3R | 3C2R | 4C1R | 5C | 5C1R | 5C2R |
| 5th-great-grandparent | 1C5R | 2C4R | 3C3R | 4C2R | 5C1R | 6C | 6C1R |
| 6th-great-grandparent | 1C6R | 2C5R | 3C4R | 4C3R | 5C2R | 6C1R | 7C |
C means cousins; R means removed. 2C is second cousins; 2C1R is second cousins, once removed. Removed counts generations, not years of age. On a narrow screen, scroll inside the chart.
Count generations, rather than birthdays
Start with the same known ancestor or ancestor couple on both sides. Count each parent-child step: a grandparent is two generations away, a great-grandparent is three, and a second-great-grandparent is four. Use the most recent shared ancestor along the branch you are comparing.
The FamilySearch cousin chart explains how to count generations from a common ancestor. For cousins, take one away from the smaller count to get the cousin number. The difference between the two counts gives the number of times removed. FamilySearch also notes that these names are mainly English-language conventions. The Genealogy Explained calculator likewise starts with each person’s relationship to a common ancestor and offers optional names for its visual explanation.
A fictional example
Jo and Sam trace one branch to the same couple. That couple are Jo’s grandparents and Sam’s great-grandparents. The counts are two and three: two minus one gives first cousins, and three minus two gives once removed. Jo and Sam are first cousins, once removed, along that branch. Their ages do not change that calculation.
Keep the people and the evidence together
A small family tree worksheet can help you count the steps. Record parents, children and sources in a family group sheet when a connection still needs checking. This calculator names the branch you enter; it does not find or verify a common ancestor.
Before you save your calculation
How do I calculate cousins once or twice removed?
Choose the shared ancestor’s relationship to each person. Grandparent and great-grandparent gives first cousins, once removed; grandparent and second-great-grandparent gives first cousins, twice removed. Both people sharing a great-grandparent gives second cousins without removal. Removed describes a difference in generations from the ancestor, not years of age.
Which family relationships can this calculator name?
It covers first through seventh cousins and up to six times removed, using a grandparent through sixth-great-grandparent for each person. Both selections must be made before a result appears. Parents, siblings, aunts, uncles, spouses and relationships through marriage are outside this calculator’s two cousin branches.
What about half-cousins or more than one shared branch?
The same generation counts can describe half-cousins, so this page does not decide half or full status. Compare a known branch at a time. An older shared ancestor may describe a more distant connection than another branch does. This is a naming calculation from your selections, not a family-link verification or a DNA-percentage calculation. Families and cultures may use different names.
Are the names and notes saved or uploaded?
Only in this page’s memory. Names are optional, and there is no account, autosave, tree upload, lookup, AI or sending. Refreshing or closing clears everything. Download text or print before leaving. Text keeps the identifying fields, selections, result and any notes you wrote, including your spacing. Saved TXT and PDF copies cannot be reopened here for editing.
Can I print a cousin chart or a blank worksheet?
Yes. Choose Print or save PDF while editing or reviewing, or use the browser menu. A completed calculation includes the two branches and the generation arithmetic. With either selection missing, it prints Not calculated and the full seven-by-seven reference chart, so you can find the relationship by hand. Written notes are included; a blank worksheet has note lines. The same chart is below the editor without making any selections. Choose Letter or A4 and check the preview, especially with long names or notes.
What do Clear and Undo restore?
Clear this calculation asks first, then clears both selections and all five text fields. Undo restores them until you change any field or close the page. Review does not remove Undo; using it there returns to editing. New selections or words after clearing retire the old Undo.
Give the connection a story
Save your calculation first. MemoirWell’s separate guided interview can help develop your own memory into an AI-assisted chapter draft to check and edit. It does not import this chart or research the people for you.
Start a free first chapter