Play unlimited Sudoku online

Play Sudoku online for free!

Play unlimited Sudoku across multiple difficulty levels right here in your browser. No registration required!

Play Sudoku

Pick a difficulty, enter numbers with keyboard or touch, and print the current puzzle whenever you want.

Ready for a new game.

ID F91BAC4B

Play Sudoku online for free

Sudoku is one of the most popular logic puzzles in the world. The goal is to fill a 9x9 grid so that every row, every column and every 3x3 box contains the digits 1 to 9 exactly once. Playing Sudoku regularly is a great way to train concentration, patience and structured thinking.

About Sudoku

Sudoku is a logic puzzle based on placing numbers in the right positions. It does not require advanced math. The challenge comes from elimination, pattern recognition and careful reasoning.

How Sudoku works

At the beginning, some cells are already filled in. Your task is to complete the remaining empty cells until the full grid is solved. A number is valid only if it does not already appear in the same row, column or 3x3 box.

A move is invalid if
  • a digit appears more than once in a row
  • a digit appears more than once in a column
  • a digit appears more than once in a 3x3 box

Sudoku tips for beginners

A few simple habits can make the puzzle easier to read and help you find safe moves more quickly.

Tip 1: start with the most complete areas

Rows, columns and boxes that already contain many digits often reveal the next move fastest.

Tip 2: check row, column and box together

A cell often becomes obvious only when you combine all three restrictions at the same time.

Tip 3: use notes instead of guessing

When several numbers are still possible, notes help you stay organized and avoid random mistakes.

Tip 4: look for repeating patterns

With practice, you will start spotting structures that let you eliminate options quickly and narrow down the right place.

Once the basic rules feel natural, Sudoku becomes a calm and rewarding flow. Starting with easy puzzles is the best way to build confidence.

Frequently asked questions

What is the best way to start as a beginner?

Start with an easy Sudoku. Focus first on rows, columns and 3x3 boxes that already contain many digits, because those usually reveal the next safe move fastest.

What should I do if I get stuck?

Move to another area of the grid and compare row, column and box again. It also helps to use notes for candidates instead of guessing.

How do the difficulty levels differ?

Easy puzzles start with more given numbers and shorter logic chains. Harder levels provide fewer clues, so solving them requires more careful deduction and longer sequences of reasoning.