What stays on this device
The game does not ask for a name, an email address, or a password. Rounds, totals, streaks, archive replays, practice sessions, and the light or dark theme are written with localStorage. Clearing site data, cookies, or the browser profile deletes them. Switching browsers or devices starts you over. There is no server copy and no support tool that can restore a streak. That limit is also stated on the Chainle FAQ.
- chainle.progress.v1 holds the in-progress or finished rounds for the daily date currently stored.
- chainle.history.v1 holds finished daily totals by date, including the five round scores and a completion timestamp.
- chainle.streak.v1 holds the current streak count, the longest streak, and the last UTC date that counted.
- chainle.theme.v1 holds "light" or "dark".
- chainle.archive.v1 holds replays of released dates. Those replays do not update the streak.
- chainle.practice.v1 holds the practice set you are in the middle of. Practice never updates the streak.
A tiny script in the page head reads only the theme key, so a dark preference can apply before the rest of the page paints. The game script reads and writes the other keys after you submit a round. Share text is built in the page and copied to the clipboard only if you press the copy button. The share text is not uploaded.
Accounts, payments, and ads
There is no registration and no payment. The first version does not include an advertising script. A comment in the page markup marks where an ad slot could be added later. If advertising is added, this policy will name the cookies that come with it before those scripts ship. Until then, playing does not set an advertising cookie.
Analytics
The site can load Google Analytics 4 when the build is given a measurement ID in the environment variable PUBLIC_GA4_MEASUREMENT_ID. The repository does not contain a real measurement ID. When the variable is missing or does not look like a GA4 ID, the analytics script is omitted entirely. When it is present, GA4 may set cookies and receive the page URL, a client identifier, and basic device data under Google's terms. You can refuse that by using a browser setting or an extension that blocks the analytics host, or by asking the site operator not to enable the ID. The game remains playable either way, because scoring does not depend on the analytics script.
Puzzle data
Released puzzles, including their listed connections, are part of the public pages. That is content, not personal data. Unreleased puzzles are not placed in the public build. Your guesses are stored only in the local keys above. They are not attached to an identity because the site does not have one for you.
Contact and deletion
Email hello@chainle.me if you have a privacy question. To delete local progress yourself, use the button on this page or clear site data in the browser. The button removes the six keys listed above and nothing else.
The terms of use describe the limits of the scores. About Chainle.me describes who reads the mail.