Solve a puzzle
Choose Easy, Medium, Hard or Master and get a board generated on your device. Write candidates as you go, ask for a hint when you are stuck, and continue later from where you stopped.
How Play worksPlay Sudoku.
Learn the logic behind every move.
SudokuLab is a Sudoku game and learning coach. Play a fresh board at four levels, ask the coach for a hint on your own grid, and learn 25 solving techniques one at a time.
Runs in your browser, with no account. Install it from the browser to play offline.
Two ways in
Study a technique
Twenty-five techniques, from the first singles to alternating inference chains, in the order you’ll meet them. Learn each one, practise it, then beat a puzzle that needs it.
How Learn worksWhat is in SudokuLab
A puzzle worth understanding
01
Every board has one solution
Every board is generated on this device, has exactly one solution and needs no guessing. Its level is set by the hardest technique it needs, not by how empty it looks.
02
Hints on your own board
Hint finds the easiest useful step on the grid you are playing. It shows the pattern, then the reasoning, then the elimination, so you can stop as soon as you see it.
03
25 techniques with walkthroughs and practice
Each technique has a worked example that lights up the cells as you read, a practice position, and a Challenge.
04
Focused and Mixed challenges
A Focused board can be finished with the technique and the ones taught before it. A Mixed board may need other techniques too, and lists them before you start.
05
Progress saved on your device
Your Play board, Challenge, Learn progress, stats and settings stay in this browser or app. Export a backup to keep a copy or move to another device.
How learning works
Every technique moves through the same three steps.
01
Learn
Watch the technique on a worked example. The cells and candidates each sentence is about light up as you read it.
02
Practise
Find it yourself on a taught position or a fresh variation: enter the digit for a single, or mark every candidate the technique removes.
03
Challenge
Solve a complete Sudoku where ordinary logic runs out and the technique gets you going again.
Your progress stays on your device
SudokuLab saves your games, Learn progress, stats and settings in this browser or app. It does not automatically upload them, and the current build has no account, analytics or advertising.
If you export a backup, you choose where the file goes. Like any website, the host that delivers SudokuLab receives ordinary connection data when you load it.
Read the privacy policyReady for a puzzle?
SudokuLab opens in your browser. There is nothing to sign up for.
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