Rainy Day Activity Generator – Online Indoor Fun for Kids
Randomly picks an indoor activity from a curated list sorted by age. No materials, no prep ideas included. Banish boredom.
UD5 Toolkit
Daily Sudoku provides a fresh, unique puzzle every single day based on the current date. Everyone playing on the same date and difficulty level gets the same puzzle, making it perfect for friendly challenges and comparing solve times with friends.
Our generator uses a seeded algorithm tied to the calendar date. This ensures the puzzle is deterministic—same date + same difficulty = same puzzle. Each puzzle has a unique solution verified by our solver. Advanced backtracking algorithms guarantee a fair and solvable challenge every time.
Easy (≈43-46 given cells) – Great for beginners. Medium (≈37-41 given) – Requires basic strategies. Hard (≈31-36 given) – Needs advanced techniques like hidden pairs. Expert (≈26-30 given) – A true challenge for seasoned solvers requiring X-Wing, Swordfish, and other advanced strategies.
Toggle Notes mode (pencil icon) to mark candidate numbers in empty cells. In Notes mode, tapping a digit adds or removes that candidate. This is essential for tracking possibilities in harder puzzles. Turn Notes off to enter final answers. Notes appear as small digits in a 3×3 grid within each cell.
Yes! Your progress is automatically saved to your browser's local storage. If you close the page and return later on the same day, your puzzle state, notes, and timer will be restored. Progress is saved per-date and per-difficulty, so you can switch difficulties and keep separate progress for each.
Start with scanning rows, columns, and 3×3 boxes for numbers that can only go in one place. Then try cross-hatching – eliminate possibilities by checking intersecting rows and columns. For harder puzzles, learn naked pairs, hidden singles, and pointing pairs. Our Hint button demonstrates these techniques on your current board.
Absolutely! Use your browser's print function (Ctrl+P / Cmd+P). The puzzle prints cleanly with the grid and given numbers. You can also screenshot the board to share with friends. All puzzles are free and regenerated daily—no subscription needed.
A red number means it conflicts with another number in the same row, column, or 3×3 box. Sudoku rules require each row, column, and box to contain digits 1-9 exactly once. Check for duplicates and adjust. Use the Check button to highlight all conflicts at once.
Randomly picks an indoor activity from a curated list sorted by age. No materials, no prep ideas included. Banish boredom.
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