Privacy Policy

Deduce is built to be played with as little personal data as possible. You can play fully anonymously; signing in is optional and only exists to save your streak across devices.

Last updated: 29 July 2026.

What we collect

• Anonymous play. When you first open Deduce we set an anonymous session cookie so we can track your streak and which puzzles you've solved. This is not tied to your name or email.
• Gameplay data. Your attempts, solve times, scores and streaks — needed to run the game, the leaderboard and your streak.
• Optional Google sign-in. If you choose "Save your streak", Google sends us a verified token from which we store a stable account identifier and your display name (and email, if provided) — only to link your progress to a durable account. We never receive your Google password.

How we use it

• To generate and validate the daily puzzle, score it fairly, and rank the leaderboard.
• To keep your streak and history, and to merge your anonymous progress into your account if you sign in.
• To understand—in aggregate—how the game is used so we can improve it.

What we don't do

• We don't sell your personal data.
• We don't run third-party advertising.
• Product analytics are privacy-minded and disabled unless explicitly enabled; event data is aggregate and contains no puzzle solutions.

Google & YouTube API Services

Deduce uses Google API services in two limited ways:

• Google sign-in (optional, described above) — used only to save your streak to a durable account.
• YouTube uploads (our own channel). Deduce's internal publishing tool uses YouTube API Services to upload our videos to our own YouTube channel (@deducepuzzles). It acts only for the account that explicitly authorizes it (scope: manage your YouTube videos) and touches no other user's YouTube or Google data.

Deduce's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. Use of YouTube API Services is also governed by the YouTube Terms of Service and the Google Privacy Policy. You can revoke Deduce's access to your Google account at any time via your Google security settings.

Data retention & your choices

You can play without an account and clear the cookie any time via your browser. To request deletion of an account created via Google sign-in, contact us (see below) and we'll remove the associated account and gameplay records.

Contact

Questions or data requests: get in touch.