You are handed a grid partly filled with digits and must complete it using pure logic, never guesswork. Each row, each column, and each of the nine boxes must contain the numbers one through nine exactly once. The given clues constrain everything, so every cell has a single correct answer.
How to play Sudoku
- Select an empty cell on the 9x9 grid
- Enter a digit from 1 to 9 that does not repeat in its row, column, or box
- Use pencil notes to track candidates for tricky cells
- Fill every cell correctly to complete the puzzle
Tips & strategy
- Scan for rows, columns, or boxes that already hold eight numbers
- Pencil in candidates for each cell to spot forced placements
- Work the easiest deductions first to open up harder regions
Controls: Click a cell, type 1-9
Sudoku — FAQ
Is guessing ever needed in Sudoku?
A well-formed puzzle always has one solution reachable by logic alone, so guessing is never required.
What do the pencil marks do?
They let you jot possible candidates in a cell without committing, which helps you reason through tougher spots.
How do you play Sudoku?
Fill the empty cells of the 9x9 grid so every row, every column, and each of the nine 3x3 boxes contains the digits 1 through 9 with no repeats. Use the clues already on the board to work out the rest.
What is the goal of Sudoku?
The goal is to completely fill the grid so that every row, column, and 3x3 box holds each digit from 1 to 9 exactly once. A correctly completed grid solves the puzzle.
Is Sudoku free to play with no download?
Yes, Sudoku runs free in any browser with no download or sign-up, and it also plays fully offline in the free Offline Games Arcade app for iOS and Android.
Any tips for solving Sudoku faster?
Scan for rows, columns, or boxes that are nearly full and place forced digits first, then use pencil marks to track candidates in tricky cells. Start with the digit that already appears most often on the board.
