Privacy Policy

Last updated: 26 September 2026

Syntene Learn ("we", "our", "us") is a free SAT Math practice website at learn.syntene.com. This policy explains what we collect and how we use it. The short version: no ads, no selling data, no tracking of you across other sites, and practice works without an account.

1. What we collect

• Progress data (answers, mastery by topic, mistakes journal, module results and custom-quiz history) linked to an anonymous device ID kept in your browser's local storage.
• If you log in with Google: your Google email, name and profile picture, so your progress follows you to another device.
• A display name, only if you set one. The app lets you choose how you appear to yourself in the app; if you set one we store it alongside your account.
• Feedback you send, so we can read and fix things. The form does not ask for an email address and we do not store one.
• Basic technical data. Our host, Cloudflare, records standard request information (such as IP address and browser type) to serve the site and stop abuse. To rate-limit abuse we also keep a hashed (one-way) form of the network address in our own database; the raw address is not stored there.

2. How we use it

• To show you your progress and study history.
• To save your progress when you log in.
• To run the free tutor limit and protect the service from abuse.
• To improve the site and its content.

We do not sell your data. We do not show ads. We do not use your data for advertising or profiling.

3. Storage and local data

We keep a device ID in your browser's local storage so your progress stays yours on this device. That progress is also stored on our servers so it can follow you when you log in. Anonymous progress is tied to that device ID and does not expire: it is only lost if you clear your browser's site data. Clearing that data may reset your device ID and hide old progress.

4. How long we keep things

• Local device data (device ID, progress, preferences): kept in your browser until you clear your browser's site data.
• Server-side progress (answers, mastery, module results, feedback): kept until you delete it (see "Your choices"). There is no automatic expiry.
• Login session cookie: expires after 30 days, or immediately when you log out. This cookie only exists if you log in; anonymous study does not create it.
• Feedback you send: kept so we can act on it, and deleted on request. No email address is collected or stored.
• Chiron, the AI tutor: we do not store the messages you type. We do keep two other things: the tutor's reply to a question, so asking the same question again is instant, and a short usage record (which question, when, which device or account asked, and a hashed network identifier) so the free daily limit and the abuse limits work. This record is deleted when you delete your data.
• Abuse counters: short-lived counts used for rate limits, cleared automatically within about a week.

5. Google login

If you choose to log in with Google, Google shares your email, name and profile picture with us. You can stop using Google login at any time and keep studying anonymously. Signing in is never required for the practice.

6. Cookies

We use at most two small, secure cookies, and only if you log in:

• sl_session: keeps you signed in. HttpOnly and Secure (page scripts cannot read it), SameSite=Lax, expires after 30 days or when you log out.
• sl_oauth: exists only during a Google login, expires in 10 minutes, and holds a one-time security code that stops forged logins.

We set no cookies of our own for advertising or tracking, and anonymous study sets none. The graphing calculator is served by Desmos, which may set its own cookies once you open it; see "Third parties" below.

7. Third parties

• Cloudflare hosts the site (Cloudflare Pages, Workers and the D1 database) and records standard server logs.
• Cloudflare, at the edge: aggregate traffic statistics such as page counts. There is no analytics script on the page, no cookies and no cross-site tracking.
• AI tutor: when you use Chiron, the question and the message you type are sent to an AI service provider that writes the reply. We do not send your name, email, device ID or account details, and we do not store your messages. The reply is kept so the same question is instant next time.
• Google provides login (OAuth) and processes your data only for that login.
• Desmos provides the graphing calculator embedded in practice questions. Opening it loads code from desmos.com, so Desmos receives a request from your browser (including your IP address) and may set its own cookies; Desmos's own privacy policy then applies to that request.
• YouTube: we link to our channel at youtube.com/@syntenelearn. Clicking that link loads YouTube, which follows Google and YouTube's own privacy policy. We do not embed YouTube tracking on the site.

8. Children

Syntene Learn is not intended for children under 13. We do not knowingly collect personal information from children under 13. If you are under 13, please do not create an account or log in with Google; you are welcome to use the site anonymously for practice. If you believe a child under 13 has provided us personal information, contact us at hello@syntene.com and we will delete it promptly. A parent or guardian can make that request on a child's behalf.

9. Your choices

• You can study anonymously without logging in.
• You can stop logging in at any time.
• Delete everything yourself, in the app: Home, then your profile picture, then Delete account. This removes your account and the data stored on our servers, including your results, feedback and tutor usage records linked to you.
• Or ask us to delete your data by contacting us (see below).

10. Changes

If what we store changes, this page changes first. The date above always reflects the current version.

11. Contact

Questions about this policy: hello@syntene.com