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
- 3 Your mother
- 7 Your mother's mother
- 15 Your mother's mother's mother
- 30 Your mother's mother's mother's father
- 61 Your mother's mother's mother's father's mother
- 123 Your mother's mother's mother's father's mother's mother
- 247 Your mother's mother's mother's father's mother's mother's mother
- 494 Your mother's mother's mother's father's mother's mother's mother's father
- 989 Your mother's mother's mother's father's mother's mother's mother's father's mother
- 1979 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother
- 3958 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father
- 7916 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father
- 15832 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father
- 31664 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father
- 63329 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother
- 126659 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother
- 253319 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother
- 506639 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother
- 1013279 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother
- 2026559 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother
- 4053119 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother's mother
- 8106238 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother's mother's father
- 16212476 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother's mother's father's father
- 32424952 Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother's mother's father's father's father
Your mother's mother's mother's father's mother's mother's mother's father's mother's mother's father's father's father's father's mother's mother's mother's mother's mother's mother's mother's father's father's father, a 22x great-grandfather, is number 32424952.