Sudoku Ninja: Classic & Killer

Contains adsIn-app purchases
811 reviews
Content rating
Rated for 3+
10K+
Downloads
Content rating
Rated for 3+
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About this game

Play Classic Sudoku and Killer Sudoku in one app! Enjoy 40,000 handcrafted sudoku puzzles, daily challenges, and relaxing offline play — a complete number puzzle experience for beginners and experts alike.

🄷 Two Sudoku Games in One
Why install two apps? Sudoku Ninja combines classic sudoku and killer sudoku, so you can switch between two popular logic puzzles anytime. Solve a quick easy grid on your commute, then take on a hard killer sudoku (also known as sumdoku, addoku, or sumoku) when you want a real brain workout.

šŸ“µ No Banner Ads — Ever
We hate interrupted thinking as much as you do. Sudoku Ninja shows no banners and no pop-ups while you solve. Ads appear only after you complete a puzzle, or when you choose to watch one for a hint. Your concentration stays unbroken from the first cell to the last.

🧩 Game Features
• 40,000 Sudoku Puzzles — endless content across both game modes
• Classic & Killer Sudoku — two number games in one app
• 5 Difficulty Levels — Easy, Medium, Hard, Expert, and Invictus for true masters
• Daily Challenges — solve the daily sudoku and earn unique rewards
• Offline Play — enjoy sudoku offline, anywhere, no wifi needed
• Magic Pencil & Autofill Notes — add and manage pencil marks instantly
• Fast Input Mode — built for experienced players
• Error Highlighting — customize how you detect and fix mistakes
• Auto-Save — pause any puzzle and resume anytime
• Cloud Sync — continue your game across devices
• Leaderboards — compete with players worldwide

šŸ”¢ How to Play Killer Sudoku
New to killer sudoku? It works like the classic number puzzle with one twist:
• Fill rows, columns, and 3x3 boxes with digits 1–9, just like classic sudoku
• Dotted lines mark ā€œcagesā€ — digits inside must add up to the number in the corner
• No repeats within a cage, row, column, or box

If you enjoy math puzzles like kakuro or kenken, killer sudoku will feel right at home. Every level is carefully balanced, so beginners learn fast while experts push their limits.

🧠 Brain Score
How sharp is your mind? Take a quick 7-minute brain test — pure visual logic, no math, no rules to memorize. Play daily for a week, then retake the test and watch your Brain Score climb. Track your progress across four skills: focus, speed, logic, and pattern recognition.

šŸ„‹ Ninja Mode
Experiment freely, like a sandbox for your brain. Mistakes are not counted or shown — perfect for testing strategies and learning. Apply your changes to the grid when ready, or roll back to your last checkpoint anytime.

ā˜• Coffee Mode
Set a time limit and race the clock! The harder it gets, the more bonus points you earn — perfect for quick, intense brain training sessions.

šŸŽØ Customization & More
• Modern design with themes, colors, and fonts
• Gentle animations and a clean grid that helps you focus
• Share your progress with friends
• Regular updates with new puzzles every week

Whether you want to unwind with an easy number game or grind expert logic puzzles, Sudoku Ninja is made for every sudoku lover. Many puzzles are handcrafted by our team to guarantee a premium experience. Download now, train your brain daily, and become a true Sudoku Ninja!
Classic & Killer Sudoku puzzles. Daily challenges, brain training & offline play
Updated on
Jul 26, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • No data shared with third parties
    Learn more about how developers declare sharing
  • No data collected
    Learn more about how developers declare collection
  • Data is encrypted in transit
  • Data can’t be deleted

Ratings and reviews

724 reviews
Kyle Fricke
July 27, 2026
I'd like to be able to see my mistake (it isn't showing despite having the "Show Mistakes" switch toggled on) . Also, the Undo function just stops working sometimes. Got to the point where I had to give up. I like the features otherwise but these features not working lead me to find an alternative.
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Sudoku Labs
July 28, 2026
Hello, thank you for your review. Mistakes are highlighted in red. Could you please send us a screenshot showing a mistake that isn't highlighted in the grid? You can send it to mnemonemo3@gmail.com.
Bikash goud
September 3, 2026
Your game is very good, but I think one option is not working correctly. When we enter a number in a row or column where the same number already exists, it is not counted as a mistake. However, when there is no duplicate number, it is counted as a mistake. I think this is incorrect. There should be an option where entering a number that already exists anywhere in the same row, column, or relevant area is counted as a mistake. Any duplicate number should be counted as a mistake.
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Tshiamo Mosime
August 26, 2026
This is the best game. I only have it and Wattpad on my phone. I spend atleast 3 hours on it after deleting TikTok, I think this game cured my doomscrolling. I do know it was updated, but the updation is not even that bad I don't know why people hate it so much.
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