Free Online Kyudoku (NineFind) - Daily Logic Puzzle Game
Welcome to Kyudoku, the addictive logic puzzle inspired by Sudoku! This brain-teasing game offers you a fresh 6×6 grid to solve every day. Use logical deduction to select 9 unique numbers while respecting one simple rule: the sum of each row and column must be less than or equal to 9. Whether you're a beginner or a puzzle expert, Kyudoku provides a stimulating challenge to train your brain and sharpen your logical thinking skills.
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Kyudoku is a logic puzzle derived from Sudoku with very simple rules. It is also known as NineFind. Each puzzle consists of a 6×6 grid of numbers, one of which is already selected (in green).
Using logical deduction (eliminating impossible choices), choose the numbers so that the sum of each row or column is equal to or less than 9. Each number (from 1 to 9) must appear only once.
The game ends when 9 unique numbers are selected on the grid and the sum rule is respected.
Strategies for Kyodoku
Here are some tips for moving forward when you get stuck:
Intersection: If two identical digits (8) are present only in a column and a row (or multiple times in the row/column), then the digit at the intersection (9) is invalid if the sum of the two is greater than 9.
Deductive Deadlock: If the 2 in L2C1 is chosen, then the 8 and 9 in C1 are invalid because S > 9. There’s an 8 and a 9 left in L5, which is impossible because S > 9, so the 2 in L2C1 is invalid. The other 2 will be chosen. 
Origin and History of Kyudoku
Kyudoku was popularized by the renowned Japanese publisher Nikoli, the company behind many beloved logic puzzles including Sudoku, Kakuro, and Slitherlink. Nikoli has been instrumental in bringing innovative number puzzles to puzzle enthusiasts worldwide since the 1980s.
The concept behind Kyudoku is elegantly simple: transform a number grid into a deductive game based on sum constraints. This innovative approach quickly captivated fans of mathematical puzzles thanks to its perfect balance between pure logic and mental arithmetic.
Today, Kyudoku (also known as NineFind) is recognized as a modern classic among number puzzles, enjoyed by logic puzzle fans around the globe. Its enduring popularity stems from the satisfying “aha!” moments when logical deductions click into place.
How Kyudoku Evolved
While Sudoku took the world by storm in the early 2000s, puzzle creators continued experimenting with number-based logic games. Kyudoku emerged as a fresh alternative that challenged players to think differently—instead of filling every cell, players must strategically select numbers while managing sum constraints. This twist created an entirely new puzzle-solving experience.
Cognitive Benefits of Playing Kyudoku
Playing Kyudoku regularly offers numerous mental and cognitive benefits that extend beyond simple entertainment:
Sharpens Mental Arithmetic
Constantly calculating row and column sums to ensure they don’t exceed 9 keeps your mental math skills sharp. This makes Kyudoku excellent practice for quick number manipulation and estimation.
Strengthens Mathematical Logic
Each puzzle requires systematic reasoning and logical deduction. You’ll develop stronger pattern recognition skills and learn to eliminate impossible solutions efficiently—skills that transfer to real-world problem-solving.
Enhances Concentration and Focus
Solving a Kyudoku puzzle demands sustained attention to detail. Regular practice helps improve your ability to concentrate on complex tasks while filtering out distractions.
Boosts Working Memory
Keeping track of multiple constraints, possible number placements, and sum totals simultaneously exercises your working memory—the mental “workspace” crucial for reasoning and decision-making.
Provides Stress Relief Through Focus
The focused mental state required for puzzle-solving creates a form of active meditation. Many players find that Kyudoku sessions help them unwind and clear their minds after stressful days.
Maintains Cognitive Health
Brain games like Kyudoku keep your mind active and engaged. Regular mental challenges are associated with maintaining cognitive function and may help keep your brain sharp as you age.
Kyudoku is particularly recommended for people who enjoy sum-based logic games, mathematical puzzles, and challenging brain teasers that combine calculation with strategic thinking.
Kyudoku vs Other Logic Puzzles – What Makes It Unique?
While there are countless logic puzzles available, Kyudoku occupies a unique space in the puzzle landscape. Here’s how it compares to other popular games:
Kyudoku vs Sudoku
Sudoku focuses on placing digits in a 9×9 grid so each row, column, and 3×3 box contains numbers 1-9 exactly once. It’s about coverage and uniqueness.
Kyudoku requires selecting specific numbers from a 6×6 grid where sums matter more than placement. You choose only 9 numbers total, making it more selective and strategic.
Key difference: Sudoku is about filling spaces; Kyudoku is about smart selection with mathematical constraints.
Kyudoku vs Takuzu
Takuzu is based on binary logic—filling grids with 0s and 1s while avoiding patterns and maintaining balance.
Kyudoku uses numbers 1-9 with sum-based constraints, requiring arithmetic thinking alongside logical deduction.
Key difference: Takuzu is purely pattern-based; Kyudoku combines patterns with mathematical calculations.
Kyudoku vs Kakuro
Kakuro (also from Nikoli) focuses exclusively on sums—filling white cells so groups add up to specific target numbers, like a mathematical crossword.
Kyudoku combines sum constraints with selection strategy—you must choose which numbers to use while respecting the ≤9 rule.
Key difference: Kakuro gives you sum targets to hit; Kyudoku requires staying under a sum limit while maximizing your selections.
What Makes Kyudoku Special
This unique combination of selection + logic + calculation makes Kyudoku a distinctive puzzle experience:
- More strategic than classic Sudoku – Every choice has cascading implications
- Faster to solve than Kakuro – Average 5-15 minutes per puzzle
- Perfect balance of math and logic – Appeals to both number lovers and logical thinkers
- Unique “selection” mechanic – Not found in most number puzzles
- Accessible yet deep – Easy to learn, challenging to master
For players seeking a fresh challenge beyond traditional Sudoku, Kyudoku offers a perfect next step that feels familiar yet wonderfully different. The mathematical twist adds an extra layer of strategic depth that keeps expert puzzle solvers engaged.
Who Should Play Kyudoku?
Kyudoku is perfect for:
- Sudoku veterans looking for a new challenge with a mathematical twist
- Math enthusiasts who enjoy puzzles that combine numbers with logic
- Students wanting to improve mental arithmetic in a fun way
- Daily puzzle solvers seeking quick, satisfying brain workouts
- Logic puzzle fans who appreciate strategic thinking games
- Anyone looking for screen-free mental stimulation (once you print them!)
Whether you’re a puzzle novice or a seasoned solver, Kyudoku’s elegant rules and engaging gameplay make it an excellent addition to your daily brain training routine.
and discover why thousands of players worldwide have made Kyudoku part of their daily routine!
Frequently Asked Questions About Kyudoku
What is Kyudoku?
Kyudoku is a logic puzzle derived from Sudoku, also known as NineFind. The goal is to select 9 unique numbers on a 6×6 grid while ensuring that the sum of each row and column is less than or equal to 9. It combines number logic with strategic thinking.
How is Kyudoku different from Sudoku?
Unlike Sudoku which uses a 9×9 grid where you fill all cells, Kyudoku uses a 6×6 grid where you select only 9 numbers. Instead of ensuring uniqueness in regions, Kyudoku requires that row and column sums don’t exceed 9. It’s a fresh take on number logic puzzles.
Is Kyudoku free to play?
Yes! Kyudoku is completely free to play on Analong.com. No registration, subscription, or payment is required. Simply visit the page and start solving daily puzzles immediately.
How do I solve a difficult Kyudoku puzzle?
Use advanced strategies like the intersection technique (eliminating impossible numbers where rows and columns meet) and the deductive deadlock method (anticipating logical dead ends). Start with rows or columns that have fewer possibilities, and work systematically through elimination rather than guessing.
Are new Kyudoku puzzles published daily?
Yes! Analong.com publishes a brand new Kyudoku puzzle every day, giving you a fresh challenge to solve and helping you build a daily puzzle-solving habit.
Can I play Kyudoku on mobile devices?
Absolutely! Kyudoku on Analong.com is fully optimized for all devices including smartphones, tablets, and desktop computers. Play anywhere, anytime with a responsive design that works perfectly on touchscreens.
What is another name for Kyudoku?
Kyudoku is also known as NineFind, referring to the objective of finding and selecting exactly 9 numbers that satisfy the puzzle’s constraints.
How long does it take to solve a Kyudoku puzzle?
Most Kyudoku puzzles can be solved in 5-15 minutes, making them perfect for quick mental breaks. As you develop strategies and improve your skills, you’ll likely solve them faster while enjoying more challenging puzzles.
Do I need to download an app to play Kyudoku?
No download required! Kyudoku plays directly in your web browser. Simply visit Analong.com and start playing immediately – no installation, no app stores, no hassle.
What are the benefits of playing Kyudoku?
Playing Kyudoku regularly helps improve logical thinking, pattern recognition, concentration, and problem-solving skills. It’s an enjoyable way to exercise your brain, reduce stress, and maintain mental sharpness through daily challenges.
Love logic puzzles? Explore our other brain-teasing games:
- Takuzu Online – Binary logic puzzle
- Anagram Plus – Word puzzle challenges
- Anagram Minus – Letter elimination game
- Daily Riddles – Test your lateral thinking
New to puzzle games? Check our Complete Game Rules Guide for all our games.
