Sudoku Puzzle

About Sudoku Puzzle: Classic Logic Game with Multiple Modes

Sudoku Puzzle is a free online Sudoku game that runs instantly in your browser with no registration needed. The classic 9×9 grid format sits at its core, but the experience stretches well beyond the standard puzzle — four difficulty levels and four distinct rule variants give both newcomers and seasoned solvers plenty to work through.

Every puzzle has exactly one solution, reachable through pure logic with no guessing required. If progress stalls, a missed step can always be traced back. Beyond solo solving, Sudoku Puzzle carries a competitive side: leaderboards track rankings by level, score, and wins, personal profiles store game history and detailed statistics, and a chat lets players connect, share strategies, and challenge each other.

Several scenes show two diagonal lines forming an X shape across the full 9×9 grid. A purple keypad with digits 1 to 9 arranged in a 3×3 square appears across multiple views of the game.

How to Play Sudoku Puzzle: Fill the Grid with Pure Logic

The goal is to fill a 9×9 grid with digits from 1 to 9 so that each digit appears exactly once in every row, column, and 3×3 box. Some cells arrive pre-filled as starting clues.

Begin with cells that have the most filled neighbors — fewer options make it easier to identify the correct digit. As cells fill in, the choices for adjacent ones narrow down, and the puzzle unfolds as a chain of logical steps.

Notes mode lets you write down multiple candidates in a single cell and eliminate them as the grid fills up. This approach is especially useful at Hard and Expert levels.

Difficulty Levels

• Easy: for beginners
• Medium: for steady practice
• Hard: for experienced players
• Expert: for those who seek a real challenge

Game Modes

• Classic: standard 9×9 Sudoku with four difficulty levels
• X-Sudoku: digits must also be unique along both main diagonals
• Windoku: extra highlighted regions apply the same uniqueness rule
• Killer Sudoku: groups of cells must add up to a given target sum
• Kropki: markers between adjacent cells define relationships — a white dot means the two digits differ by 1, a black dot means one is exactly twice the other

Games You Might Like

If number puzzles keep you coming back, Block Blast 2048 offers a calm, logic-driven challenge where merging numbered blocks at your own pace shares the same satisfying step-by-step thinking as Sudoku. For tile-matching at a relaxed tempo, Mahjong Classic delivers a solitaire puzzle with a guaranteed-solvable random layout every time, much like Sudoku Puzzle's single-solution guarantee.

Browse the full Puzzle games collection for more logic-based challenges, or head straight to the Sudoku games category for more grid-filling variants. Number fans will also find plenty to explore in the Math games section.