Cousin calculator: what relation is my cousin? KINSHIP
Say what the shared ancestor is to each of you, and get the name of the relationship both ways, a drawing of the two lines, and the share of DNA to expect on average.
The two people
How they are related
The cousin chart
Choose a square to see it worked out above.
How it works
How cousins are counted
Two people are cousins when neither descends from the other and neither is the other's brother, sister, aunt, uncle, niece or nephew. Count the generations from each of them up to the ancestor they share. Take the smaller of the two numbers and subtract one: that is the degree, so grandchildren of the same grandparents are first cousins and great-grandchildren of the same couple are second cousins. The difference between the two numbers is how many times removed they are.
A relationship is half when the two descend from one shared ancestor rather than from a couple: half-siblings share one parent, and the children of half-siblings are half first cousins. A great-aunt is also called a grandaunt; both are in use, and the page gives both.
The share of DNA is what the generations give on average: each generation passes on half, so first cousins share an eighth and second cousins a thirty-second. Real people vary around those figures, and the further apart they are the more they vary. No centimorgan figures are given, because the amounts real pairs share overlap so much between relationships that a single figure would mislead.
It names a relationship from the generations you give it. It does not read a family tree (GEDCOM on this site opens one) and it does not work out a relationship from a DNA match. Double cousins, related through two lines at once, are two relationships: work each one out.
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