Terms of use
Last updated: 19/10/2026.
The service
A Thousand Surnames is a free, for-fun tool that works out surnames from a family tree. It is provided as is, without warranties: results depend on the tree’s data, and INE statistics are indicative.
Your data and your family’s
You are responsible for the data you enter. Before you share an image or file with other people’s details, especially living people’s, make sure they don’t mind.
Third-party data
Surname frequencies come from Spain’s National Statistics Institute (INE) and are reused with attribution. Ancestry and MyHeritage are trademarks of their owners, who are not connected with this site.
Google Drive
Google Drive sync is optional and uses your own Google account, under Google’s terms. It keeps there an encrypted copy that only your recovery code opens: if you lose it together with every device, nobody can recover that copy, us included. Keep your own backups from time to time too.
Changes
We may update these terms. The date above shows the latest version.