We collect as little as possible and never sell your data.
For anonymous visitors we store test results (reaction times, scores, device category, input method) with no personal identifiers. If you create an account we also store your email, username, and any country you choose to share.
Country and region are always optional and changeable. You can use ReactionLab and take every core test without providing any personal information.
Your recent history, personal best, streak, and preferences are stored in your browser's local storage so they work even without an account.
Account details, saved test sessions, achievements, streaks, leaderboard records, and challenges you create or accept.
Only server-validated results appear on leaderboards, and only your username and (if you opt in) country are shown. We never display your email or precise location.
You can sign in with email/password or Google. Passwords are hashed and never stored in plain text. Sessions are secured with signed tokens.
You can request deletion of your account and associated data at any time. Local data can be cleared by clearing your browser storage.