SUDOKU

Number Logic · Brain Puzzle · Classic

About the Game

Sudoku is the world's most popular logic puzzle. The goal is to fill a 9 × 9 grid so that every row, every column, and every 3 × 3 box contains the digits 1 through 9 exactly once. No maths involved — only pure logical deduction from the starting clues already placed on the board.

Popularised by newspaper puzzle sections in the 1980s and 2000s, Sudoku quickly became a global phenomenon with hundreds of millions of regular players. The browser version brings the same calm, focused challenge to any screen — now coming to GameZone as a free online game, no download or account required.

Planned Features

• Four difficulty levels — easy, medium, hard, expert
• Daily challenge puzzles with a fresh unique puzzle every day
• Pencil-mark / candidate note system for tracking possibilities
• Error highlighting — optional instant feedback on incorrect entries
• Hint system for when you get stuck
• Undo and redo functions
• Timer and personal best times per difficulty
• Mobile-optimized number pad and cell selection
• Bilingual interface — English and German language toggle

Game Mechanics

Each puzzle begins with a partially filled 9 × 9 grid. The pre-filled clue numbers are fixed — only the empty cells need to be completed. Every digit from 1 to 9 must appear exactly once in each of the nine rows, each of the nine columns, and each of the nine 3 × 3 sub-grids. The intersection of these three constraints creates a unique logical solution for every valid puzzle.

Solving techniques range from simple single-candidate elimination for easy puzzles all the way to advanced pattern recognition methods for expert-level grids. No guessing is ever required — every step can be proven by logic alone.

Why GameZone

• 100 % free — no fees, no in-app purchases, no premium tier
• No signup, no account, no email required
• No download, no install — runs instantly in any modern browser
• Works on desktop, laptop, tablet, and smartphone
• No personal data collected, no tracking cookies, no third parties
• Private, non-commercial project — built for the love of classic games
• Growing collection of arcade and classic games — all free, all in your browser