Privacy

Last updated 2026-10-31

Your progress stays on your device

Concepts you have learned, your review cards and your practice code are stored in your browser's local storage. They are not sent to us. Clearing your browser data deletes them.

No cookies from us

Engrain sets no cookies and has no accounts.

Visitor counter

To count unique visitors per day, our server combines your IP address with a secret that changes every day, hashes the result, and throws the IP away. The hash cannot be turned back into your IP and cannot be linked across days. Known bots are not counted. We never store IP addresses.

Anonymous learning events

When you mark a concept learned, or get a prediction wrong, the page may send an event with only the concept ID — no user ID, no device ID. We use these to find pages that confuse people.

Reports you send

“Report an error” and “Something missing?” send the text you type and the page address. Do not include personal details.

Microphone

“Say it out loud” records in your browser only. The recording is never uploaded and disappears when you leave the page.

Ads

Ads are not running yet. When they start, they will come from Google AdSense, and only at the end of a concept page or in the side column. Where the law requires it you will be asked for consent first; if you say no, you get non-personalised ads. Google may use cookies for ads; see how Google uses information from sites that use its services.

Contact

Questions: use “Report an error” on this page.