Privacy Policy
Last updated: 24 September 2026
Who we are
IB Math Lab is operated by Prepalio International B.V. (KVK: 42134936), the data controller for the information described here. Contact: hello@ibmathlab.com.
What we collect
When you apply: your name, email address, phone number, the student’s name, current and target grade, and anything you write in the notes. When you enrol: the same details plus your payment, which is processed by Stripe (we never see card numbers). When you request a referral code or reserve a seat, we also compute a technical identifier from your browser and device settings (a hash, nothing readable) so that a referral code cannot be used by the person it was issued to; it is used for nothing else. During the course: attendance, the student’s work on the shared whiteboard, and recordings of teaching sessions, which may include the student’s voice and video.
Guide downloads
When you ask for one of our guides: your first name, your email address and, if you give it, your child’s current grade. We use them to send you the guide. We send you emails about the course only if you tick the separate box for that, and you can unsubscribe at any time. These details are kept for 12 months.
How we use it
To arrange the intro call, run the course, contact you about it (schedule, setup guide, updates at the midpoint and the end), process payment and send receipts. We do not use your details for anything else and we do not sell or rent them.
Recordings
Teaching sessions are recorded so students in that cohort can rewatch them. Recordings are shared only with the enrolled students of that cohort and are deleted within six months of the course ending. Lab sessions are not recorded.
Third-party services
Stripe (payments), Vercel (hosting and cookieless analytics), PostHog (how visitors use this site; see Cookies below, and every form input is masked in session replays), our email provider (transactional email), and the video-call and whiteboard tools used for sessions, which are named in the setup guide. Each has its own privacy policy.
Data retention
Application details are kept for 12 months. Enrolment and course records are kept for the course plus 12 months, then deleted on request. Payment records are kept as required by Dutch tax law.
Your rights
Under the GDPR you can ask to access, correct or delete your personal data, or receive a copy of it, at any time. Email us and we’ll handle it within 30 days.
Cookies
Vercel Analytics and, until you choose, PostHog work without cookies or stored identifiers. The Google tag also loads before you choose, but sets no cookies and sends Google no identifiers until you accept: only anonymous signals (for example that a page was viewed or a form was sent after an ad click), which Google uses to estimate how many people an ad brought. If you accept cookies in the banner, PostHog keeps an identifier and records sessions (with every input masked) so we can see where the site is confusing, and the Meta pixel and the Google tag set their cookies to measure how our advertising performs. We do not use them to show you personalised ads. If you decline, none of that happens. You can change your choice at any time by clearing this site’s data in your browser. Stripe may set cookies on the checkout page for fraud prevention.
Measuring our ads
When you apply, start a checkout or pay, we record which ad you came from (the campaign tags in the link, and the ad click code) with your application or payment, so we can see what each ad costs per family. If you accepted cookies, we also tell Meta and Google from our server that the application or payment happened, so that they can match it to the ad: we send your email address and phone number only in hashed form (a one-way code), your IP address and browser type, and the cookie identifiers of their pixel and tag. If you declined, nothing is sent to them from our server. Meta and Google handle this under their own terms and privacy policies.
Contact
Any privacy question or request: hello@ibmathlab.com.