Last updated 8 September 2026
The short version. TI-84 Chat runs in your browser and talks to your calculator and your AI provider directly. Your provider key is readable only by you: if you switch on sync, it is encrypted on your own machine with a passphrase we never see. If you use the hub, your messages are stored so the people in the room can read them.
The app is a static web page. When you connect a calculator it talks to it directly over USB using your browser's Web Serial support, and when you ask a question it calls your chosen AI provider directly from your browser. Neither of those goes through a server we operate, because there isn't one.
You supply your own key for whichever AI provider you use. It is stored in your browser on the device you typed it into, and it is sent only to that provider, as part of your requests. We never see it.
You can optionally switch on sync, which makes your keys available on any device you sign in to. When you do, your browser encrypts them with a passphrase you choose — AES-GCM, under a key derived with PBKDF2 — and only the encrypted result is uploaded. The passphrase is never sent anywhere, so what our database holds is a blob that nobody with access to it, ourselves included, can open. That is also why there is no recovery: lose the passphrase and those stored keys are gone, and you would clear the vault and add your keys again.
What you type on the calculator, and what the model replies, pass through your browser and go to your AI provider. We do not receive, log or store them. They are subject to the privacy policy of the provider you chose — Groq, OpenRouter or Google — and you should read theirs, because that is where your conversations actually go.
Signing in is optional; talking to your own calculator never needs an account. If you do:
If you join a room, the messages you send there are stored so that the people in that room can read them, including later. That is what a chat room is. Only members of a room can read its messages, which the database enforces rather than the page — but treat anything you type in a room the way you would treat anything else you have handed to other people.
We do not store the conversations you have with an AI provider, or anything else on your calculator.
There are none. No analytics, no advertising, no third-party trackers, and no cookies beyond the session cookie that keeps you signed in if you chose to sign in.
Email the address below and we will delete your account and everything associated with it. You can clear the key vault yourself at any time from your account page, and clearing this site's data in your browser removes the local copy of your keys.
The app is aimed at students and is safe to use without an account. Signing in requires an email address; if you are under 13, please use it signed out.
If this policy changes in a way that affects what we collect, the date at the top changes with it.
Questions or deletion requests: cameron.maclaurin@icloud.com