Home › Guides › Sudoku Rules

sudoku hint nyt

The Basics

Sudoku is a logic-based number puzzle that has become one of the world's most popular brain games. Despite using numbers, no math is required—only logical deduction and pattern recognition.

The goal is simple: fill a 9×9 grid with digits 1-9 following three basic rules. Each puzzle has a unique solution that can be reached through logic alone—never guessing.

💡 Key Fact

The name "Sudoku" comes from Japanese, meaning "single numbers" (数独, sūdoku). However, the modern puzzle was actually invented by an American architect, Howard Garns, in 1979.

The Three Rules

Every Sudoku puzzle follows exactly three rules:

1

Each Row Contains 1-9

Every horizontal row must contain each digit from 1 to 9 exactly once. No repetition allowed.

2

Each Column Contains 1-9

Every vertical column must contain each digit from 1 to 9 exactly once. No repetition allowed.

3

Each 3×3 Box Contains 1-9

Each of the nine 3×3 sub-grids (boxes) must contain each digit from 1 to 9 exactly once.

✅ Pro Tip

Think of it this way: every row, column, and box is like a container that needs exactly one of each number 1-9. If a number already exists in that container, it can't appear again.

Understanding the Grid

A standard Sudoku grid consists of:

  • 81 cells arranged in a 9×9 grid
  • 9 rows running horizontally
  • 9 columns running vertically
  • 9 boxes (3×3 sub-grids) outlined by thicker lines
534678912 672195348 198342567 859761423 426853791 713924856 961537284 287419635 345286179

Blue numbers are given clues; gray numbers are solved by the player

How to Start Solving

Follow these steps when approaching a new puzzle:

  1. Scan the grid - Look for rows, columns, or boxes that have many given numbers
  2. Find obvious placements - If a row/column/box is missing only one number, fill it in
  3. Use elimination - For each empty cell, determine which numbers are possible
  4. Look for singles - Find cells where only one number can go
  5. Repeat - Keep scanning and eliminating until the puzzle is complete

Basic Techniques

1. Scanning (Crosshatching)

Look at each number (1-9) and scan where it can go in empty boxes. Use the existing numbers in rows and columns to eliminate possibilities.

2. Naked Singles

When a cell has only one possible candidate after eliminating all numbers that appear in its row, column, and box, that candidate must go there.

3. Hidden Singles

When a number can only go in one cell within a row, column, or box—even if that cell has other candidates—that number must go there.

Tips for Beginners

✅ Do's

• Start with easy puzzles and gradually increase difficulty
• Use pencil marks to note possible candidates
• Take breaks when stuck—fresh eyes help
• Double-check each number placement

⚠️ Don'ts

• Never guess—Sudoku is pure logic
• Don't place a number unless you're 100% sure
• Avoid the temptation to look at solutions
• Don't give up—every puzzle has a solution

Frequently Asked Questions

Do I need to be good at math?

No! Sudoku uses numbers as symbols, but requires no mathematical calculations. You could use letters, colors, or shapes instead.

Can a Sudoku puzzle have multiple solutions?

A properly constructed Sudoku puzzle has exactly one unique solution. If a puzzle has multiple solutions, it's considered flawed.

Is guessing ever necessary?

Never. Every valid Sudoku puzzle can be solved through pure logic. If you feel the need to guess, you may have missed a logical deduction.

sudoku packing method

archive Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly. portland press herald sudoku There are several difficulty levels in Sudoku, ranging from easy for beginners to expert for seasoned players. Solving techniques include scanning, cross-hatching, and identifying candidate numbers.

archive Advanced Sudoku Solving Techniques

how do u play sudoku

archive Advanced Sudoku solving methods involve complex patterns like X-Wing, Swordfish, and XY-Wing. These techniques are often required for hard and expert level puzzles. sudoku tips advanced strategies Playing Sudoku daily has many cognitive benefits, including improving memory, concentration, and logical reasoning skills. It is a great way to keep the brain active and healthy.

archive Advanced Sudoku Solving Techniques

blocks sudoku

archive Sudoku competitions are held globally, where speed solvers compete to finish complex grids in the shortest time possible. sudoku game medium level Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly. can sudoku have multiple solutions Sudoku variants like Killer Sudoku, Jigsaw Sudoku, and Sudoku-X provide additional challenges for players looking for something different from the classic version.

archive What is Sudoku and How to Play?

how to solve sudoku faster

archive Playing Sudoku daily has many cognitive benefits, including improving memory, concentration, and logical reasoning skills. It is a great way to keep the brain active and healthy. sudoku porn Advanced Sudoku solving methods involve complex patterns like X-Wing, Swordfish, and XY-Wing. These techniques are often required for hard and expert level puzzles. microsoft sudoku daily challenge Playing Sudoku daily has many cognitive benefits, including improving memory, concentration, and logical reasoning skills. It is a great way to keep the brain active and healthy. teacher sudoku Advanced Sudoku solving methods involve complex patterns like X-Wing, Swordfish, and XY-Wing. These techniques are often required for hard and expert level puzzles.

archive How to Solve Hard Sudoku Puzzles Step by Step

beginner sudoku

archive Sudoku competitions are held globally, where speed solvers compete to finish complex grids in the shortest time possible. sudoku hints and tips The rules of Sudoku are simple but the depth of the game is immense. Every well-posed Sudoku puzzle has a unique solution that can be reached through logical deduction. sudoku addition Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly.

archive History of the Sudoku Puzzle

killer sudoku medium

archive The rules of Sudoku are simple but the depth of the game is immense. Every well-posed Sudoku puzzle has a unique solution that can be reached through logical deduction. web sudoku evil Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly. web sudoku evil Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly. sudoku online printable free Sudoku variants like Killer Sudoku, Jigsaw Sudoku, and Sudoku-X provide additional challenges for players looking for something different from the classic version. sacramento bee sudoku To solve a Sudoku puzzle, one must look for cells where only one number is possible, or rows/columns/blocks where a specific number has only one possible placement.

archive Advanced Sudoku Solving Techniques

pocket sudoku

archive Many people enjoy solving Sudoku as a relaxing hobby. It provides a sense of accomplishment when a difficult puzzle is finally completed correctly. how many combinations of sudoku are there Modern Sudoku was popularized by Nikoli in Japan in the 1980s. It has since become a global phenomenon, with daily puzzles appearing in newspapers and online platforms worldwide. sudoku pdf free print Modern Sudoku was popularized by Nikoli in Japan in the 1980s. It has since become a global phenomenon, with daily puzzles appearing in newspapers and online platforms worldwide. sudoku solver from picture Advanced Sudoku solving methods involve complex patterns like X-Wing, Swordfish, and XY-Wing. These techniques are often required for hard and expert level puzzles.

archive How to Solve Hard Sudoku Puzzles Step by Step

samurai sudoku printable free

archive Modern Sudoku was popularized by Nikoli in Japan in the 1980s. It has since become a global phenomenon, with daily puzzles appearing in newspapers and online platforms worldwide. sudoku challenger Playing Sudoku daily has many cognitive benefits, including improving memory, concentration, and logical reasoning skills. It is a great way to keep the brain active and healthy. sudoku printable grids The rules of Sudoku are simple but the depth of the game is immense. Every well-posed Sudoku puzzle has a unique solution that can be reached through logical deduction. extremely hard sudoku printable Sudoku is a logic-based, combinatorial number-placement puzzle. The objective is to fill a 9x9 grid with digits so that each column, each row, and each of the nine 3x3 subgrids contain all of the digits from 1 to 9. medium sudoku with answers To solve a Sudoku puzzle, one must look for cells where only one number is possible, or rows/columns/blocks where a specific number has only one possible placement.

Related Topics

sudoku coffee maker sudoku restaurant sudoku online hard loco sudoku printable games usa today sudoku puzzle free printable sudoku puzzles easy

🔍 Related Searches

sudoku 4x4 sudoku online evil pro sudoku sudoku 10000 free very very easy sudoku Average Sudoku Intersection Removal Easy Sudoku Last Remaining Cell Challenging Sudoku Easy Sudoku Online Standard Sudoku