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
- 495 Your mother's mother's mother's father's mother's mother's mother's mother
- 990 Your mother's mother's mother's father's mother's mother's mother's mother's father
- 1981 Your mother's mother's mother's father's mother's mother's mother's mother's father's mother
- 3963 Your mother's mother's mother's father's mother's mother's mother's mother's father's mother's mother
- 7926 Your mother's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father
- 15853 Your mother's mother's mother's father's mother's mother's mother's mother's father's mother's mother's father's mother
- 31707 Your mother'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
- 63415 Your mother'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
- 126831 Your mother'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
- 253662 Your mother'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 father
- 507325 Your mother'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 father's mother
- 1014651 Your mother'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 father's mother's mother
- 2029303 Your mother'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 father's mother's mother's mother
- 4058606 Your mother'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 father's mother's mother's mother's father
- 8117213 Your mother'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 father's mother's mother's mother's father's mother
- 16234427 Your mother'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 father's mother's mother's mother's father's mother's mother
- 32468855 Your mother'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 father's mother's mother's mother's father's mother's mother's mother
- 64937711 Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother
- 129875423 Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother's mother
- 259750847 Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother's mother's mother
- 519501694 Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother's mother's mother's father
- 1039003389 Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother's mother's mother's father's mother
Your mother'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 father's mother's mother's mother's father's mother's mother's mother's mother's mother's mother's father's mother, a 27x great-grandmother, is number 1039003389.