At Try Sudoku, your privacy is our top priority. This Privacy Policy explains how we handle your information
when you use our Sudoku puzzle service. Try Sudoku offers both local-only gameplay (no account required) and optional cloud-synced features (requires account).
Information We Collect
Without an Account (Local Storage Only)
If you play without creating an account, we store the following information locally on your device:
Puzzle progress - Current game state, pencil marks, hints used
Game statistics - Puzzles played, completed, best times, streaks for each difficulty
User preferences - Theme selection, sound settings, timer visibility
Daily challenge status - Completion tracking and daily streaks
Important: This data is stored locally in your browser's localStorage and is not transmitted to any server.
With an Account (Cloud Storage)
If you create an account, we collect and store the following on our servers:
Account information:
Username (required, publicly visible on leaderboards)
PIN (required, stored as a secure hash - we cannot see your actual PIN)
Email address (optional, used for account recovery)
Country code (optional, displayed as a flag on leaderboards)
Gameplay data:
Game statistics (puzzles played, completed, best times, streaks)
Leaderboard entries (times, rankings by difficulty level)
Achievement progress and unlocked achievements
Level progression and XP earned
Daily challenge history and completion streaks
Preferences: Theme, sound settings, and other options synced across devices
Technical data: Session tokens, last login time, sync timestamps
Anonymous Usage Statistics (Coming Soon)
We plan to collect anonymous, aggregated gameplay statistics to improve our puzzles and provide interesting insights to players. This may include:
Overall completion rates by difficulty level
Average puzzle completion times
Most popular difficulty levels
General solving patterns
This data will be fully anonymized and cannot be used to identify individual players.
How We Use Your Information
Local Data (No Account)
Local data is used solely to:
Track your personal puzzle statistics
Remember your preferences
Enable game features (hints, notes, undo)
Track daily challenge progress
Cloud Data (With Account)
When you create an account, we use your data to:
Provide cloud sync - Synchronize your progress across multiple devices
Display leaderboards - Show your username, times, and country flag publicly
Track achievements - Record your achievement progress and unlocks
Level progression - Calculate and display your level and XP
Anti-cheat - Detect and prevent fraudulent time submissions
Service improvement - Aggregate anonymous statistics to improve the puzzles
Public Information
If you create an account and use leaderboards, the following information will be publicly visible:
Your username
Your puzzle times and rankings
Your country flag (if provided)
Your level and achievements (may be visible in certain features)
Your daily challenge streaks
Your email address, PIN, and other account details are never publicly visible.
Third-Party Services
We use the following third-party services:
Cloudflare: Hosting, content delivery, and DDoS protection
Cloudflare D1: Database storage for account and game data
Google Fonts: Typography (your browser connects to Google's servers)
Font Awesome: Icons via CDN
We do not use:
Advertising networks or ad trackers
Social media tracking pixels
Third-party analytics services that track individual users
Cookies
Try Sudoku does not use tracking cookies. We use:
localStorage: For game data and preferences
Session tokens: Stored in localStorage for authentication (if logged in)
Data Storage and Security
Local Storage
Local data (without account):
Stored in your browser's localStorage
Never transmitted to any server
Protected by browser same-origin policy
Can be cleared through browser settings
Not backed up - clearing browser data deletes it permanently
Cloud Storage
Account data (with account):
Stored on secure servers hosted by Cloudflare
PINs are hashed using industry-standard algorithms (never stored in plain text)
Data transmitted using HTTPS encryption
Session tokens expire for security
Access restricted to authenticated requests only
Data Retention
Local data: Retained until you clear your browser data
Account data: Retained as long as your account exists
Game history: Retained for statistics and anti-cheat purposes
Deleted accounts: Data is deleted within 30 days of account deletion request
Your Rights
You have the right to:
Play without an account: Full gameplay without providing any personal information
Access your data: View your account information and statistics
Clear local data: Delete local storage through your browser settings
Delete your account: Request complete deletion of your account and associated data
Export your data: Request a copy of your data in a portable format
Opt out of leaderboards: Stop participating in public rankings at any time
Children's Privacy
Our puzzles are suitable for all ages. We do not knowingly collect personal information from children under 13. Account creation is optional and requires only a username and PIN. We recommend parents supervise their children's use of online features.
Changes to This Privacy Policy
We may update this Privacy Policy from time to time to reflect changes in our practices or for legal reasons.
We will post any changes on this page with an updated "Last Updated" date. Since we don't collect email
addresses from all users, we cannot notify everyone directly of changes.
International Users
Our servers are located globally through Cloudflare's network. By creating an account, you consent to your data being processed and stored in data centers that may be located in different countries.
Do Not Track
Try Sudoku respects Do Not Track (DNT) browser settings. We do not use third-party tracking services that would be affected by DNT signals.
Contact Us
If you have questions about this Privacy Policy or our privacy practices, you can contact us through the
following channels:
