Generate · play · solve

Sudoku from scratch

Make a fresh puzzle with one guaranteed solution, play it with pencil notes and hints, or type your own and let the solver finish it.

00:00

Tap “New puzzle”, or type your own and press Solve.

5 Given clue 5 Your / solved entry 5 Conflict or wrong

Generator seeds the three diagonal boxes, then expands by backtracking — the valid form of the box-by-box “seed and grow” idea — and removes cells only while a single solution survives. Solver uses a most-constrained-cell heuristic. Saves and runs as a static .html or .php file; everything runs in your browser.

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Line up the puzzle

Drag the four corners to the edges of the grid, then read it. Straight-on, well-lit photos read best.

Lay the page flat and fill most of the frame.
Even light, no glare or heavy shadow across the grid.
Use Rotate if the photo came in sideways.