Shikaku: How to play using Flash

Problem list Rules How to play

Start window of Shikaku

This shows the screen when you start a problem. The bottom-right timer starts when you open the problem.

This is the solving mode so you can start right away.

Generally use the left mouse button.

Change line width

Change the line width of the game grid here.

Settings of thin line

Remove the check mark in the "Grid" button and the grid lines disappear.

Display area or notDisplay area or not

Check the "Area" button to display the area when you are dragging.

The number of selected cells appears only with 4 or more cells.

Your settings for these buttons will be saved to preserve your playing environment.

On some computer systems the settings may not be saved.

Zoom function

You can enlarge and move the game board with these buttons.

Play using the mouse

Generally use the left mouse button when you play Shikaku puzzles.


When dragging, the selected cells become light blue.

Stopped dragging

When you release the mouse button after dragging, your selected rectangle (box) will color. If the area and hint (the number) are different the color is light gray.

Stopped dragging

If the area and hint are equal the color becomes dark gray.

Stopped dragging

If the selected rectangle (box) violates the rules the rectangle becomes light gray. Never 2 numbers in a rectangle and never no number either!!

Expanding area

You can enlarge your selected rectangle (box).

Try dragging from different points in a rectangle (box). The final shape will depend on where you start, where you finish, and also on the original shape.

Here the dragging starts from the corner (bottom right) and expands the rectangle (box).

Clicking rectangle

Clicking on a rectangle (box) will deselect it (remove the coloring). Only a newly dragged rectangle will remain selected.

By dragging, existing rectangle will be destroyed

Also, if you drag across existing rectangles (boxes) they will be deselected (color goes) and only the one you newly dragged will remain.

Look to the left to see how it works. If you want to clear a large area, drag across the area to be cleared and click in this large rectangle.

Clear button

When you want to start a puzzle again click the "Clear" button. The timer does not return to zero though. To reset the timer you have to close the problem and open it again.

The members page counts the number of times you open a puzzle.

Undo button

When you want to redo a step, click the "Undo" button. By clicking this button repeatedly you can return to the start.

Check button

After solving a problem, click the "Check" button. If your solution is correct the screen will say "Congratulations." If your solution is not correct it will indicate one point that is not correct, click the "Continue" button to continue to solve this puzzle.

How to use Try-mode

Check button

When you want to put a box temporarily thinking about the next step, use Try-mode. Click the "Try" button and the screen changes to Try-mode.

With the Try-mode, you can solve problems just like in the regular solving-mode, only your first line is brown and the following all yellow.

Cancel trying button

Click the "Delete" button in Try-mode, if you want to delete your trial actions. All your trial actions then disappear.

Fix trying button

Click the "Fix" button in Try-mode if you want to set (make permanent) your trial actions. The color of all your trial actions are changed to dark grey and you return to the solving-mode.