Privacy policy
Last updated: 3 February 2026
TL;DR: We only store what we need to run your account (email + course access), your progress (so you can pick up where you left off), and anonymous aggregate stats (which questions people find hardest). We don't sell your data. We don't run third-party ads. You can delete everything by emailing us.
1. Who runs this site?
IB Math Revision is a solo teacher-run site by Pete Bromfield, based in the UK. If you have any question about your data, just email pbromfield@ibmathrevision.com — the same person who wrote every question on the site will read it.
2. What we store, and why
| What | Why we need it | Where it lives |
|---|---|---|
| Your email address | To sign you in, save your progress, and email your receipt / weekly digest. | Firebase Authentication (Google Cloud, EU region). |
| Your display name + avatar (if you sign in with Google or Microsoft) | To personalise the top-nav. | Firebase Authentication. |
| Which courses you own + purchase dates | To unlock the right content. | Firestore (Google Cloud). |
| Your practice attempts + scores | To show you your progress, streak, and weakest topics. | Firestore. |
| Anonymous router-quiz analytics (browser session ID, quiz answers, chosen stream, whether you bought) | To A/B test whether our quiz actually helps visitors pick the right course. Never linked to your name. | Firestore (preib_router_events). |
| Payment records (last 4 digits of card, amount, invoice) | Legal requirement to keep receipts. | Stripe (never touches our servers). |
3. Who else sees your data
We share as little as possible. The only third parties involved are:
- Firebase — hosts our sign-in, database and cloud functions (Google, EU).
- Stripe — processes card payments. We never see your card number.
- Resend — sends transactional emails (receipts, weekly digests). We give them your email address and the email body.
- No advertising networks. No Meta / TikTok / Google Ads pixels. No profiling.
4. Cookies
Only a handful, and only for site function:
- Firebase auth cookies — keep you signed in.
localStorage— remembers your quiz result, A/B variant, free-preview counter, and "snooze the banner" choice. Never sent to us.preib_router_events— anonymous session ID for A/B analytics (browser-only, never tied to your email).
Third-party ad cookies: none. Tracking pixels: none.
5. How long we keep it
- Course access + purchase records: as long as you have an active subscription, plus 7 years for tax records (legal requirement).
- Practice scores + progress: until you ask us to delete them.
- Anonymous router-quiz events: 30 days rolling.
6. Your rights (UK GDPR)
- Access — ask for a copy of everything we hold about you.
- Correction — ask us to fix anything wrong.
- Deletion — ask us to delete your account and all data. We'll do it within 30 days.
- Portability — ask for your data in machine-readable JSON.
- Complaint — you can complain to the UK Information Commissioner's Office if you're unhappy with how we handle your data.
To exercise any of these, email pbromfield@ibmathrevision.com — no forms, no jargon, just ask.
7. Changes
If we change this policy in any meaningful way, we'll email everyone with an active account. Small clarifications will just get a note at the top of this page.