Choose your puzzle

Puzzle setup 3
Dimensions

3D

Five layers.

The rows and columns continue through the stack.

Rules

Classic: every number once on every line. Inequalities: signs between neighbouring cells also show which number is smaller.

Numbers per line
5
Difficulty
50

Board view

Choose two dimensions for the board. The others become sliders. Your selected cell stays the same.

Hints & checks

Aids for large boards

These use only your entries, never the answers. Undo reverses each one in a single step.

Saved puzzles

Pick up any puzzle where you left off. Entries, pencil marks, and undo history stay with each attempt.

Puzzle details

Difficulty describes the techniques used to solve the starting puzzle. Every rated puzzle has a complete logical solution without guessing. Navigation is separate from the rating.

Ratings are an initial guide; we’re still calibrating how they feel to players. Earlier saved puzzles remain unrated.

Keyboard shortcuts

1–9
Enter a number or pencil mark
Arrow keys
Move between cells
N
Toggle pencil marks
Delete
Erase the selected cell
Page Up / Down
Change layer
Shift + Page Up / Down
Change world
] / [
Next or previous board with empty cells
Ctrl / ⌘ + Z
Undo
Ctrl / ⌘ + Shift + Z
Redo
Esc
Close a menu or dialog

Settings

This copy of Soodokoo runs entirely on this device. Nothing is sent anywhere.

Delete your data from the server?

This removes your name, your daily results and ranking, any solve times you shared and, if you’re signed in, your account and the puzzles kept with it. You’re signed out, and this device gets a new random ID.

Saved puzzles and achievements on this device are not affected.

How to play

Each number belongs once in every line, along every dimension.

In 2D, solve the rows and columns on a single board. There are no Sudoku boxes.

In 3D, those rules extend through a stack of boards. Move the Layer slider to compare cells at the same row and column.

In 4D, a World contains a stack of layers. Change worlds to follow another direction through the puzzle.

In 5D, a Galaxy slider connects sets of worlds, and in 6D a Universe slider connects sets of galaxies. Every direction follows the same rule.

From 3D up, Stack and Cube show the whole puzzle at once. Stack lays your layers out as sheets of paper; Cube floats every cell in its place. The lines through your cell take one colour per direction, and beyond 3D the other worlds stand beside yours. Drag to turn, pinch to zoom, and tap a cell to go there.

Beside the board, a strip for each slider shows your cell at every position along it, and the map shows every board; tap either to go there. In Stack and Cube, where the board is out of sight, Row and Column strips join them, in the same colours as the lines. In 3D, All layers lays every layer out as its own board.

Inequalities puzzles add signs between neighbouring cells. A sign points at the smaller number: in 2 < 5 it points at the 2, and ∧ points up at the cell above. Signs sit on the rows and columns of each board, never between layers, so these puzzles keep their board’s two directions.

Select an empty cell and enter a number. Use Pencil to add your own notes. The game doesn't add notes or flag mistakes automatically.

Hint, under the number pad, shows where to look first, then the idea, then the answer; checks are under More. Pause from More, or press P. Your puzzles save separately in this browser. Undo and Redo survive reloads for the most recent 2,000 edits in each attempt.

Paused