3D Sudoku — Play Sudoku on a Cube
Regular Sudoku is a flat grid. 3D Sudokuwraps the same rules around all six faces of a rotating cube. Rows and columns still can't repeat a number — but here they bend over the cube's edges and continue onto the neighbouring face. The moment you rotate the cube, a flat puzzle becomes a spatial one.
How is 3D Sudoku different from classic Sudoku?
You already know the rule: no repeats along a line. What changes is the shape of the line. On the Cubedoku cube, a line starts on one face, folds over an edge, and carries on across the next face. Cells on edges and corners belong to several lines at once, making them the puzzle's key intersections — a structure flat Sudoku simply doesn't have. You're doing number logic and mentally rotating a solid at the same time, which is exactly why it works the brain harder than a flat grid.
Start at 3³, work up to the full 9³
The smallest 3³ cube takes minutes to learn and is the friendly way in if you've never tried a Sudoku cube before. Sizes step up from there to the full 9³ — six interlocking 9×9 faces, a genuine challenge for experienced Sudoku solvers. Difficulty is adjustable independently, so beginners and veterans both have a sensible starting point.
Three ways to play the cube
Cubedoku builds three modes around the cube. The Cube is the standard 3D Sudoku — pure spatial logic. Avalanche splits the big cube into 3³ sub-cubes that collapse block by block as you complete them — Sudoku meets match-3. In Blitz, a starting clue disappears every few seconds, testing how fast you can reason under pressure. Alongside them you'll find classic flat Sudoku, Killer Sudoku and Skyscraper — six modes in total, plus a fresh daily challenge.
Free, no download, no account
3D Sudoku plays right in your browser on phone, tablet or desktop. There's nothing to install and no sign-up — the core game is completely free. An account is only needed if you want to join the leaderboards.