Generators4 min read
Play Sudoku: 450 Unique Puzzles Offline
Play Sudoku with 150 puzzles per difficulty (easy, medium, hard) in the MyDevTools break room. Sign in to save progress.
Get the tool mentioned in this guide in the desktop app:Sudoku
Sudoku rules
1. Fill a 9×9 grid so every row, column, and 3×3 box contains digits 1–9. 2. Each number appears exactly once per row, column, and box. 3. Some cells are pre-filled; these are givens. 4. No arithmetic required; pure logic.
How to play
- Click a cell to select it.
- Type a digit (1–9) or use arrow keys to navigate.
- Highlight conflicts — impossible numbers are grayed out.
- Check progress — see if you've completed rows/columns.
- Clear cell — delete or press backspace.
Difficulty levels
- Easy — many givens, logical deduction only.
- Medium — fewer givens, requires planning.
- Hard — minimal givens, advanced techniques needed.
450 puzzles (150 per level) keep you challenged without repeats.
Strategies
- Naked singles — find cells with only one possible value.
- Hidden singles — find values that fit only one cell in a row/column/box.
- Pairs/Triples — eliminate candidates by logical inference.
- Advanced — X-wings, Y-wings, swordfish (look these up if interested).
Frequently asked questions
Can I get hints?
Highlighting conflicts is the main aid. Hint buttons or solver features may be added.
Can I undo moves?
Click to clear cells. Full game undo may come later.
Is there a timer?
Yes, tracks solve time. Compete against yourself to improve.