Privacy
The Arithmoí Foundation keeps as little as it can about you. This page says what, why, where, and for how long.
Who we are
This website is run by The Arithmoí Foundation, a US 501(c)(3) non-profit organization.
Write to us at admin@arithmoi.org, or by post: The Arithmoí Foundation, c/o Athene Noctua Press, 4745 Arapahoe, Suite 300, Boulder, Colorado 80303, USA.
What the site collects, and only that
Newsletter. Your email address, the words you agreed to and the date, the page and language of the sign-up, and the dates of confirmation and of unsubscription. For subscribers who joined before this site, the original sign-up date and where it came from.
Contact form. Your name, your email address, your message, and the page and language you wrote from.
Technical. A one-hour hash of the visitor's address, kept only to limit abuse. The address itself is not kept.
Where it is kept
In the Foundation's own database on Cloudflare. Emails are sent through Resend. The site's pages are published from GitHub, which holds no visitor data.
What the site does not do
- No cookies.
- No analytics and no trackers.
- No advertising and no third-party scripts.
- Nothing is sold or shared.
Your choice of look, light or dark, stays in your own browser and goes nowhere.
How long it is kept
- A sign-up that is never confirmed is deleted after 7 days.
- An address that has unsubscribed is kept only as proof of that choice.
- Messages from the contact form are kept for 12 months, then deleted.
Your rights
Every email carries a one-click unsubscribe. You may ask to see, to receive a copy of, or to delete what we hold about you: write to admin@arithmoi.org.
Children
Nothing here needs an account to be read. The newsletter is not meant for children under 13.
Other Arithmoí sites
The school and the library have their own privacy pages.
In effect from 15 October 2026.