Frequently Asked Questions

Slitherlink (数回) is a logic puzzle where you draw a single continuous loop by connecting dots. The numbers in each cell indicate how many lines should surround that cell. The goal is to create one closed loop that satisfies all the number clues.

Click the 'Sign Up' button in the top right corner. You'll only need an email address and a display name for the leaderboards. Account creation is free and gives you access to daily challenges and progress tracking.

You can play puzzles without an account, but creating one unlocks features like daily challenges, progress tracking, leaderboard participation, and the ability to save your game history.

1) Draw a single continuous loop connecting the dots. 2) Numbers indicate how many lines should surround that cell. 3) The loop cannot branch or cross itself. 4) Every line segment can only be used once. 5) The loop must close completely on itself.

Left-click on the edge between two dots to draw a line. Left-click again on the same edge to remove it. You can also drag to draw multiple connected lines quickly.

Right-click or long-press on an edge to mark it with ×. This indicates you're certain no line should go there. It's a helpful strategy to mark edges you've ruled out. Right-click again to remove the mark.

Blue lines are your drawn lines. Green lines indicate correct placement (when you're close to the solution). Red lines show conflicts or errors. Numbers turn green when their requirement is satisfied and red when there are too many surrounding lines.

New daily challenges are released every day at midnight UTC (Coordinated Universal Time). The difficulty follows a weekly pattern: Monday (Easy 5×5), Tuesday (Medium 7×7), Wednesday (Hard 10×10), Thursday (Medium 7×7), Friday (Master 12×12), Saturday (Ninja 15×15), Sunday (Hard 10×10).

Currently, daily challenges are only available for the current day to maintain the competitive aspect. However, you can play similar difficulty puzzles from our regular puzzle library anytime.

We designed the weekly cycle to accommodate different skill levels and provide variety. It starts easy on Monday and gradually increases, with weekend challenges being the most difficult. This gives everyone a chance to participate throughout the week.

Your score is calculated based on: Base points (varies by difficulty) + Time bonus (faster completion = more points) - Error penalty (50 points per mistake). The minimum score is 100 points. Viewing the solution disqualifies your score from competitive leaderboards.

We have four leaderboard types: Daily (today's best scores), Weekly (this week's total), Monthly (this month's total), and All-Time (overall best). Each shows the top 100 players plus your personal ranking.

Leaderboards update in real-time when you complete a puzzle. Your score is automatically submitted if you have an account and haven't viewed the solution.

Yes! All leaderboards are currently free to view and participate in. We believe competitive puzzle solving should be accessible to everyone.

Slitherlinks works on all modern browsers (Chrome, Firefox, Safari, Edge) on desktop and mobile devices. The game is optimized for touch screens and supports both mouse and touch input.

Puzzle generation uses advanced algorithms to ensure quality. Most puzzles load in under 2 seconds. If you experience consistent delays, try refreshing the page or switching to a different puzzle difficulty.

Currently, display names are set during account creation. If you need to change yours, please contact us at [email protected] and we'll help you update it.

Yes. We use industry-standard encryption for all data transmission and storage. Passwords are securely hashed, and we never store them in plain text. Read our Privacy Policy for complete details about data handling.

Yes, you can request account deletion by emailing us at [email protected]. We'll remove all your personal data within 30 days, though leaderboard entries may be retained for competitive integrity.

We use advanced constraint satisfaction algorithms powered by the Choco Solver engine. Every puzzle is automatically verified to have exactly one valid solution before being added to our database.

This would be a serious bug. Please contact us immediately at [email protected] with the puzzle details. We'll investigate and fix the issue quickly. Quality is our top priority.

Difficulty is determined by grid size and puzzle complexity: Easy (5×5), Medium (7×7), Hard (10×10), Master (12×12), and Ninja (15×15). Larger grids generally require more advanced solving techniques.

We're focused on perfecting the classic Slitherlink experience first. Future updates may include variations like triangular grids or different loop constraints based on community feedback.

Our roadmap includes user profile enhancements, social features for sharing achievements, mobile app development, and accessibility improvements. Follow our changelog for the latest updates.

Absolutely! We love hearing from our community. Send your ideas to [email protected] or through our contact form. Many current features came from user suggestions.

Currently, we're a web-based platform optimized for mobile browsers. A dedicated mobile app is in our development plans for 2026.

Not yet, but it's a highly requested feature on our development list. We're working on theme options including dark mode and high contrast modes for better accessibility.

Try refreshing the page. If the problem persists, clear your browser cache or try a different browser. Make sure JavaScript is enabled. Contact us if issues continue.

The puzzle automatically adjusts to your screen size. Try zooming in with your browser (Ctrl/Cmd + +) or switching to landscape mode on mobile devices for better visibility.

Progress is automatically saved to your account when logged in. If you were playing as a guest, progress isn't saved. Make sure you're logged in before starting puzzles.

Scores are only submitted if you're logged in and complete the puzzle without viewing the solution. Check that you have an active account and completed the puzzle legitimately.