Privacy policy

If you practice without an account

Your answers, scores, and settings are saved in your own browser's storage, on your device. They never reach our database. Clearing your browser data erases them. Our hosting provider (Vercel) counts page visits with cookieless analytics that do not identify you, and our servers apply short-lived, IP-based rate limits to a few endpoints to prevent abuse; those entries are deleted automatically within days.

If you create an account

We store:

• your email address, a display name if you choose to set one, and a hashed password (we cannot read your password);
• your practice progress: which questions you answered, your scores, streak, study settings, and practice-test results — so they sync across your devices;
• if you sign in with Google, the email and name Google shares. We get no access to anything else in your Google account.

That is the whole list. No advertising profiles, no location tracking, no contact lists, no selling or renting data to anyone, ever.

The AI tutor

When you ask the tutor to explain a question, the question and your answer are sent to Anthropic (our AI provider) to generate the explanation. We send the content of the exercise — not your name, email, or any account details.

Email

We send account emails (confirmation, password reset) and, for active accounts, a short weekly progress summary. Every summary email has a one-click unsubscribe link, and unsubscribing never affects your account. We never send marketing for other companies.

Cookies

One cookie, and only after you sign in: the session cookie that keeps you logged in. No advertising cookies and no third-party trackers. The visit counting mentioned above works without cookies.

Who processes data for us

Like nearly every website, we run on infrastructure providers: Vercel (hosting and cookieless visit counts), Neon (database), Resend (sending the emails above), Cloudflare Turnstile (bot protection on signup), and Anthropic (AI explanations). Each receives only what its job requires and none may use your data for its own purposes.

Students and parents

Most of our users are teenagers, and the product is designed accordingly: the collection above is the minimum an account needs, there is no behavioral advertising, screens are never recorded, and everything works without an account at all. Parents can email us at any time to ask what we hold about their child or to have it deleted.

Your rights, wherever you live

Email hello@hit1600.com from your account address and we will send you a copy of everything we hold about you, correct it, or delete your account and all of its data entirely — usually within days, at most within 30. These rights are yours regardless of country; we apply the same standard (the EU's GDPR, the strictest we operate under) to everyone.

Changes

If this policy changes in any way that matters, the date at the top changes and account holders are told by email before the change takes effect.