Play / puzzles·1× card
Sudoku
4×4 for little kids, 6×6, then easy 9×9 — always one unique solution. Answer key stays off the paper.
Example
🔒 The answer is never printed — it shows in the app (and via the page's QR code).
How to play
- Fill every empty square so each row, each column and each box has every number exactly once.
- Start with rows, columns or boxes that are almost full. Every puzzle has exactly one answer, so no guessing needed.
- Check your answer in the app.
How it works
Procedurally generated, then dug so every grid has exactly one solution — a real sudoku, not a guessing game.
What you can set
- Appropriateness dial (kindergarten → adult) — tune it per card. Scales 4×4 → 6×6 → easy 9×9 and how many blanks.
Age dial (1–20): 1–6: 4×4 grid · 7–13: 6×6 · 14+: 9×9. More blanks as it climbs.