Ancestor Numbers
An Ancestor Number (the proper name is an Ahnentafel number) says exactly where a direct ancestor sits in your family tree. You are always number 1. Anyone's father has double their number, and their mother double plus one: so your father is 2 and your mother 3, your father's parents are 4 and 5, your mother's parents 6 and 7, and so on. That's why every man in your tree (apart from you) has an even number and every woman an odd one.
Entering the Ancestor Numbers of your direct ancestors on My Ancestors keeps your records accurate, helps your cousins work out how they're related to you, and tells apart two lines that happen to share a surname.
Print our Ancestor Chart Every box on the chart shows its number, five generations back from you.
Peter Calver, who founded LostCousins, explained Ancestor Numbers in his newsletter of 25 December 2023 (Why are your female ancestors odd?).
Find a number by stepping back from you
Choose father or mother, one generation at a time, until you reach the person you want.
- 1 You
- 2 Your father
- 5 Your father's mother
- 11 Your father's mother's mother
- 22 Your father's mother's mother's father
- 44 Your father's mother's mother's father's father
- 89 Your father's mother's mother's father's father's mother
- 179 Your father's mother's mother's father's father's mother's mother
- 358 Your father's mother's mother's father's father's mother's mother's father
- 717 Your father's mother's mother's father's father's mother's mother's father's mother
- 1435 Your father's mother's mother's father's father's mother's mother's father's mother's mother
- 2871 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother
- 5743 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother
- 11486 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father
- 22973 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother
- 45947 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother
- 91894 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father
- 183789 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother
- 367579 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother
- 735159 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother
- 1470319 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother
- 2940639 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother
- 5881279 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother
- 11762559 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother
- 23525119 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother
- 47050238 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father
- 94100476 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father's father
- 188200952 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father's father's father
- 376401904 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father's father's father's father
- 752803808 Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father's father's father's father's father
Your father's mother's mother's father's father's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother's mother's mother's mother's mother's mother's mother's mother's father's father's father's father's father, a 27x great-grandfather, is number 752803808.