Can I play Sudoku on a phone?
Yes. Tap a cell and use the number pad below the grid. The tool buttons and number keys are sized for touch, and the board fits a narrow screen.
Cozy web games
Sudoku
Sudoku gives you a fresh 9 by 9 puzzle at Easy, Medium, or Hard difficulty. Use notes while you work, undo a move, ask for a hint, and keep your best time for each level in this browser.
Controls: Tap an empty cell, then tap a number below the board. Notes, Undo, Erase, and Hint have separate touch buttons.
PCder pick
Sudoku is a stable catalog pick.
This page is one of the games PCder is comfortable recommending first: the controls are clear, the source trail is visible, and the game fits a desktop browser session.
Regional page
Play Sudoku in Australia
This Australia page is tuned for quick desktop breaks and no download browser play. Fill the grid with one of each number in every row, column, and box. PCder keeps the controls, source note, and licence status nearby.
Quick answer
Sudoku online
Sudoku is a 9 by 9 number puzzle split into nine 3 by 3 boxes. Fill every empty cell so each row, column, and box contains the numbers 1 through 9 once. This version creates puzzles with one solution and includes notes, hints, undo, sound, three difficulty settings, and local best times.
- Best for
- Play a free Sudoku puzzle with notes, hints, difficulty settings, and touch controls.
- Related searches
- Sudoku online, free Sudoku game, Sudoku puzzle with notes, mobile Sudoku browser game
How to play
How to play Sudoku
- Choose a difficulty Select Easy, Medium, or Hard. A new puzzle appears when you change the setting.
- Select an empty cell Tap or click a blank space. The game shades its row, column, and 3 by 3 box.
- Enter a number Choose a number from 1 through 9. It must not repeat in the same row, column, or box.
- Complete the grid Fill every blank cell correctly. The game records your time and keeps the best result for that difficulty in this browser.
Player guide
Start with the most restricted spaces
Look for a row, column, or 3 by 3 box that is missing only one or two numbers. Those spaces give you the fewest possibilities and the safest first entries.
- Use Notes when a cell has two or three possible numbers.
- A placed number removes that candidate from notes in the same row, column, and box.
- Switch difficulty when you want a new puzzle with more or fewer starting clues.
Solving tip
Use candidates instead of guessing
Check which numbers already appear in a cell's row, column, and box. Any missing number blocked by those three groups cannot go in the cell. Notes help you keep the remaining candidates visible.
- Scan rows and columns with only a few empty cells first.
- When a number can fit in only one cell inside a box, place it there.
- Use Hint for one answer without revealing the rest of the puzzle.
Common questions
Sudoku FAQ
Does every Sudoku puzzle have one solution?
Yes. The generator removes clues one at a time and checks the remaining grid. It keeps a removal only when the puzzle still has exactly one solution.
What does Notes mode do?
Notes mode adds or removes small candidate numbers without filling the cell. When you place a correct number, the game clears that candidate from related cells.
How are Easy, Medium, and Hard different?
The settings aim for about 42, 34, and 28 starting clues. The generator may keep an extra clue when removing it would create another solution.
Does Sudoku save my progress?
The current puzzle lasts while the page stays open. The game saves only your best completion time for each difficulty in local browser storage.
Is this Sudoku game open source?
Yes. It is an original PCder game released under the MIT license. PCder hosts all of its HTML, CSS, and JavaScript.
Can I play Sudoku on PCder from Australia?
Yes. The Australia page keeps Sudoku ready for desktop browser play, with no launcher and no account step. Some schools, offices, and managed networks may still block game sites.