Our commitment to a fair, honest, and respectful competitive environment for every player.
At Sudoku Challenge, we believe that competition should be a test of skill and logic — not who has the best external tools. Every feature of our anti-cheating system is designed to level the playing field and ensure that victories reflect genuine puzzle-solving ability.
Anti-Cheating Measures
Our platform implements multiple layers of protection to maintain competitive integrity across tournaments and duels:
Global Solver Blocking
When a puzzle is live in a tournament, a duel, the Classic Daily Challenge or the Daily Triple, it is blocked from our Solver tool globally across all devices and browsers worldwide. This means nobody — not even someone on a different computer — can use our Solver to cheat on an active competitive puzzle. The Solver displays information about the active event and when the puzzle will become solvable again.
Focus Detection & Board Blurring
During tournaments and duels, if you switch tabs, minimize the browser, or move focus away from the game window, the puzzle board automatically blurs. This prevents players from copying the puzzle to external solver tools, taking screenshots, or switching to other websites. The board unblurs instantly when you return — but the timer keeps running during the blur period.
No Pause in Competitive Play
The timer cannot be paused in tournaments, duels, the Classic Daily Challenge or the Daily Triple. All players compete under identical time constraints with no exceptions. Time continues running even when the board is blurred, ensuring that leaving the game window carries a real cost.
Unique Puzzles, Same for Everyone
Each tournament and duel generates its own unique set of puzzles that cannot be pre-solved or predicted. Puzzles are generated deterministically on the blockchain, ensuring every participant receives exactly the same puzzle — guaranteeing a completely fair playing field.
One Account, One Timed Game
Each player can be in only one timed competitive game at a time — a tournament, a duel, the Classic Daily Challenge or a Daily Triple puzzle. You cannot start another while one is in progress, or use multiple accounts. Usernames are globally unique and case-insensitive to prevent impersonation.
Automatic Replay Checks
Every competitive game — the Classic Daily Challenge, the Daily Triple, tournaments and duels — is saved as a replay, and each replay is checked automatically. Someone solving places each digit wherever their next deduction is, stops to think before the hard cells, and works with pencil marks and colours. Someone copying a solver's answer types it in reading order at an even, steady beat, placing cells the board does not show yet. Only when several of these signs agree is a replay flagged. A flagged Daily or Daily Triple result can be kept off the public leaderboard for that day; flagged tournament and duel replays are reviewed by hand. Solving styles that end in a fast run of placements — colouring a board until it resolves, then filling it in, or placing one digit in many cells at once — are taken into account. A held-back result still counts in the player's own history, nothing else changes, and the next fair solve is ranked as normal.
Rating Integrity
Our competitive rating system (used in tournaments and duels) uses an Elo-style algorithm with several safeguards to ensure fair rankings:
Duel Margin Awareness
Rating changes account for how close the match was, not just who won. A narrow loss costs less than a blowout.
Rating Convergence
New players have higher volatility (K-factor), allowing ratings to stabilize faster. Established players have more stable ratings.
Fair Matching
Duel matchmaking pairs players within a similar rating range to ensure competitive and enjoyable matches.
Admin Oversight
Administrators can review suspicious activity and adjust ratings if manipulation or abuse is detected.
Community Guidelines
Sudoku Challenge is a community for players of all ages and backgrounds. We expect all members to behave with respect and sportsmanship. The following behaviors are not tolerated:
Offensive, abusive, hateful, or discriminatory language of any kind
Harassment, threats, or personal attacks against other players
Spam, advertising, or irrelevant content in reviews or feedback
Impersonation of other players, moderators, or administrators
Attempting to exploit bugs or vulnerabilities for competitive advantage
Any form of cheating, including the use of external solving tools during competitive play
These guidelines apply everywhere on the platform, including usernames, feedback reviews, and any public-facing content.
Content Moderation
To maintain a safe and welcoming environment, all user-generated content on Sudoku Challenge — including feedback, reviews, and usernames — is subject to our content moderation system:
Automatic word filtering blocks profanity, slurs, hate speech, and other inappropriate language in your browser and on our servers.
All submitted feedback and reviews are screened before being made visible. Content that violates our guidelines will be rejected with a clear explanation.
We reserve the right to remove any content — including reviews, ratings, and usernames — that violates our community guidelines, at our sole discretion and without prior notice.
Players who repeatedly violate community guidelines may have their accounts suspended or permanently banned by administrators.
Enforcement Actions
Our administrators have the tools to maintain a fair and respectful platform. Enforcement actions may include:
Warning
A private notice for minor first-time violations
Rating Adjustment
Correction of ratings affected by manipulation
Temporary Ban
Suspension from competitive play for repeated offenses
Permanent Ban
Account termination for severe or persistent violations
Report a Violation
If you suspect unfair play, encounter abusive behavior, or discover a bug that could be exploited, please let us know. We take every report seriously and investigate thoroughly.
No system is perfect, and we continuously improve our anti-cheating measures. But our greatest asset is the community itself. Play fair, play honest, and enjoy the game!