Privacy policy

Effective date: November 1, 2026

Kin & Number is an educational website about mathematics in anthropology. This policy explains what information the site handles, why, and what you can do about it. It is written for readers in the United States, and we apply the same practices to everyone.

Reading the site

You can read everything on Kin & Number without an account, and we do not ask who you are.

We do not use analytics services, advertising networks, tracking pixels or any other tool that follows you around the site or across the web. We do not build profiles of readers.

We do keep a simple count of our own. When you leave a page, or switch away from it, your browser sends our server one short note about that page: how many seconds it was on your screen, how far you scrolled, its address, the general kind of place you came from (a search engine, an AI assistant, another website or nowhere in particular) and the country your connection appears to be in, as our network provider reports it. The note is linked only to a random code that your browser invents for that page and forgets when the page closes; we use it so that a second note from the same page updates the first instead of counting twice, and we erase it after two days. No cookie, IP address or browser details are stored with the note, and if your browser sends a Do Not Track or Global Privacy Control signal, it sends no note at all.

Like almost every web server, ours keeps technical logs of the requests it receives: the IP address that made the request, the page asked for, the date and time, the browser's user agent string and the referring page, if any. We use these logs only to keep the site secure and working, for example to spot abusive traffic or trace an error. They are kept for a short time and then deleted. The site is also served through a network provider that filters malicious traffic before it reaches us, and it processes the same kind of request information for that purpose.

The site has a sign-in page for the small team that edits it. When someone tries to sign in, the IP address and the username entered are recorded so that repeated password guessing can be blocked. Those records are used for nothing else and are kept only for a short time.

Writing to us

When you use the form on our contact page, we store what you send: your name, your email address, an organization if you choose to give one, your message and the date it arrived. We use this only to read your message and reply to it, including passing a question about a particular piece to the person who wrote it. A copy of each message is also sent to the team's mailbox so that it is seen quickly; it is handled there under the same rules.

To keep out automated spam, the form (and the team's sign-in page) runs Cloudflare Turnstile, a check that looks at technical signals from your browser to tell people from bots. It runs only on those two pages, and Cloudflare handles that information under its own privacy policy.

We do not add you to a mailing list, and we do not sell or rent what you send. Messages are kept while we are dealing with them and for a reasonable time afterward, so that a correction or a longer conversation can be followed, and then deleted. You can ask us to delete your message at any time.

Cookies

We do not set cookies for readers. The only cookie of our own is a strictly necessary session cookie for team members who sign in to edit the site. The network provider mentioned above may set a short-lived security cookie if it needs to check that a visitor is not an automated program. The cookie policy has the details.

Affiliate links

Some links to books and shops are affiliate links: if you follow one and buy something, we may earn a commission at no extra cost to you. When you click such a link, you leave Kin & Number. A partner network such as CJ Affiliate may then set its own cookies in your browser to record that the visit came from us, so that a commission can be credited. Those cookies, and any information those companies collect, are governed by their own privacy policies, not this one.

The reports we receive from these programs show clicks, orders and commissions in summary form. They do not tell us who you are.

When you click one of these links, your browser also sends us a short note naming the kind of box the link sat in, for example the reading shelf at the end of an explainer. We add one to that box's count for the day and for the country the click came from, as our network provider reports it. Nothing else about you is kept: no IP address, page address or cookie is stored with it. The counts tell us which reading lists readers find useful.

What we do not do

• We do not sell personal information.
• We do not share personal information for targeted or cross-context behavioral advertising.
• We do not use personal information to make automated decisions about anyone.

Children

Kin & Number is written for a general audience of students and adults and is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has sent us information through the contact form, tell us and we will delete it.

Your choices and rights

You can ask us what information we hold about you, ask us to correct it, or ask us to delete it. Residents of California and several other US states have specific rights under state privacy laws, including the rights to know, correct and delete personal information and to opt out of its sale or sharing. Because we do not sell or share personal information, there is nothing to opt out of, but every other request is welcome. We will not treat you differently for making one.

To make a request, write to us through the contact page using the email address you want the request to cover, so that we can match it to our records.

Security

The site is served only over encrypted connections, the editing area is limited to the team, and the database that holds contact messages is not reachable from the public web. No system is perfectly secure, but we keep what we store small, which limits what could ever be exposed.

Changes to this policy

If we change how the site handles information, we will update this page and its effective date. Significant changes will be described at the top of the page for a reasonable period.

Contact

Questions about this policy go through the contact page.