Sudoku
Nine rows, nine columns, nine boxes, and one way to fill them. A fresh daily puzzle and unlimited grids from Easy to Expert.
Sudoku is a free puzzle game you can play instantly in your web browser on a phone, tablet or computer, with no download and no sign-up. Classic 9×9 Sudoku from Easy to Expert, plus a new daily puzzle. Notes, hints and undo.
- Genre
- Puzzle, Logic
- Controls
- Tap a square, then a number
- Plays on
- Phone, tablet and computer
- Price
- Free, no account needed
How to play Sudoku
Sudoku is played on a 9×9 grid divided into nine 3×3 boxes. Some squares start with a number. Fill every empty square with a digit from 1 to 9 so that:
- every row contains 1 to 9 exactly once,
- every column contains 1 to 9 exactly once, and
- every 3×3 box contains 1 to 9 exactly once.
You never need to guess. Every puzzle here is generated in your browser and checked to have exactly one solution, so each square can be worked out by logic.
Controls
| Action | Phone or tablet | Computer |
|---|---|---|
| Select a square | Tap it | Click, or the arrow keys |
| Enter a digit | Tap 1 to 9 on the number pad | 1 to 9 |
| Pencil notes | Notes button, then digits | N toggles notes |
| Erase | Erase button | Backspace, Delete or 0 |
| Hint | Hint button | H |
| Undo | Undo button | Z |
Difficulty levels and the daily puzzle
- Easy (about 40 given digits): ideal for beginners. Most squares can be filled by scanning.
- Medium (about 33): you will need pencil notes now and then.
- Hard (about 28): expect pairs and careful elimination.
- Expert (about 24): very few clues and long chains of logic.
- Daily puzzle: one Medium grid per day, the same for everyone. Solve it on consecutive days to build a streak.
Helpful features
- The row, column and box of the selected square are highlighted, and so is every copy of the same digit.
- Wrong digits turn red and count as mistakes. There is no mistake limit, so you can keep going.
- Placing a correct digit removes it from the pencil notes in the same row, column and box.
- The number pad shows how many of each digit are still missing.
- Your game saves automatically, so you can close the tab and continue later.
Sudoku tips
- Start with the digit that appears most often. Scan each box for where that digit can still go.
- Look for a single candidate. If only one digit fits a square, place it.
- Look for a hidden single. If a digit can only go in one square of a row, column or box, it goes there.
- Use notes on harder grids. Pencil in all candidates, then look for pairs: two squares in a unit that can only hold the same two digits.
For more, read our Sudoku tips for beginners.
Questions
Is this Sudoku free?
Yes. It is free with unlimited puzzles, works in your browser on any device and needs no account or download.
Does every Sudoku have only one solution?
Yes. Each grid is checked by a solver before you see it, so there is always exactly one correct answer.
How long does a Sudoku take?
Most people finish an Easy grid in 5 to 15 minutes and a Medium grid in 10 to 25 minutes. Hard and Expert grids can take 30 minutes or more.
Do hints affect my best time?
Best times are only recorded for puzzles solved without hints, so they stay a fair record of your skill.
