Puzzle
Sudoku online
Fill the 6×6 or 9×9 grid so every row, column and box holds each number once. Solve solo at four levels or race friends on the same puzzle.
Sudoku guide
The classic number puzzle in 6x6 and 9x9: solve solo at your level, or race friends on the very same grid.
What is Sudoku?
Sudoku is a number placement puzzle: fill the grid so every row, column and box holds each number exactly once. On DD Games you can solve 9x9 or 6x6 puzzles solo at Easy, Medium, Hard or Expert, race 2 to 6 players online on the same puzzle, or play the Daily Sudoku with its own leaderboard.
Every puzzle on DD Games is generated with exactly one solution, so it can always be solved by logic. The level is simply the number of given cells: 9x9 runs from 40 givens on Easy to 22 on Expert, and the smaller 6x6 grid from 22 down to 14, which makes it a quick puzzle for beginners.
The race mode turns Sudoku into a two player (or up to six player) duel. Everyone gets the same puzzle and solves their own copy at the same time; you see how far the others have got, never their numbers.
For a puzzle a day, the Daily Sudoku is one 9x9 grid for everyone: easier early in the week, hardest on Sunday, with a timer and a daily leaderboard.
How to play Sudoku
- Choose Play solo for a puzzle at your own pace, or Play online to race 2 to 6 players who all get the same puzzle.
- Pick a grid and a level. 6x6 (boxes of 2 rows by 3 columns): Easy 22, Medium 18 or Hard 14 given numbers. 9x9 (3x3 boxes): Easy 40, Medium 32, Hard 26 or Expert 22.
- Tap an empty cell, then a number on the pad. The row, column and box of the selected cell light up, along with every cell holding the same number.
- Turn on Notes to pencil small candidate numbers into a cell. When you place a number, that note disappears from its row, column and box.
- Fill every cell so each row, column and box holds every number exactly once. On a keyboard use the arrow keys, 1 to 9, Backspace and N for notes.
Rules
- Each row, each column and each box must contain every number from 1 to 6 (6x6) or 1 to 9 (9x9) exactly once.
- Every puzzle has exactly one solution, and the level is the exact number of given cells.
- Numbers are checked as you place them. A wrong number turns red and counts as a mistake; the third mistake ends the puzzle. Correct numbers lock in place.
- Solo puzzles give you 3 free hints; more hints use a hint helper from the Gem shop. A hint fills in the cell with the fewest possible numbers.
- Undo is free in solo play but does not take back a mistake.
- In an online race the first player to fill the whole grid wins. A third mistake puts a racer out, and races have no hints or undo.
- A race also ends when everyone is out or after 10 minutes (6x6) or 30 minutes (9x9). Players still in rank ahead, then most correct cells, then fewest mistakes.
- The Daily Sudoku is 9x9 with no hints, and three mistakes end the run.
Tips and strategy
- Look for a number that can only go in one place in a row, column or box; that is often quicker than looking for a cell with only one option.
- Start with the numbers that already appear most often: the count under each pad key shows how many are left.
- Use notes on harder levels. Two cells in a unit that can only hold the same two numbers rule those numbers out of the rest of the unit.
- Never guess in a race: three wrong numbers put you out.
- New to Sudoku? Start with 6x6 Easy to learn the scanning habit, then move to 9x9.
Questions
Can you play Sudoku against a friend?
Yes. Open an online room for 2 to 6 players and the host picks the size and level. Everyone races on the same puzzle, and the first to fill the grid wins.
How does a Sudoku race work?
Everyone in the room gets the same puzzle and solves their own copy at the same time. You only see how far the others are, never their numbers.
Is there a new Sudoku every day?
Yes. The Daily Sudoku is one 9x9 puzzle for everyone, Easy on Monday and Tuesday up to Expert on Sunday, with a timer and a daily leaderboard. It resets at midnight IST.
Does every Sudoku have one solution?
Yes. Each puzzle is built by removing numbers from a full grid only while the puzzle keeps exactly one solution, so it can always be solved by logic.
What is the difference between the Sudoku levels?
The number of given cells. 9x9 Easy starts with 40 numbers and Expert with only 22; 6x6 runs from 22 down to 14.
What happens if I make three mistakes in Sudoku?
The third wrong number ends the puzzle. In a race it puts you out, and players still in rank ahead of you.
Do I earn rewards for Sudoku?
Solo puzzles earn a little XP for signed-in players, and your best times per size and level are saved on your device. Online races earn XP and Gems like other online games.
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