Sudoku: How to play using Flash

Sample problemsRulesHow to play

Start window of Sudoku

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.

You can play Sudoku by mouse only or by keyboard only. Also you can choose a cell by mouse and put the number by keyboard. Enjoy solving in your favorite manner.


Change line width

Change the line width of the game grid here.


Changing mode of Bar

Remove the check-mark in the "Bar" button and the "Number Bar" doesn't appear on the display. If you want to insert numbers by keyboard, it's better to take off this check-mark.


Enable or Disable Memo

Remove the check-mark in the "Memo" button and you cannot put temporary numbers. Expert players will do well to remove this check-mark.


On or Off Number

Put a check-mark in the "Number" button and the numbers from 1 to 9 appear on the display. When you finish to put a number in all the nine 3 x 3 boxes, correct or not correct, the color of this number will lighten.


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

On some computer systems the settings may not be saved.


Play using the keyboard

Disable Bar

Remove the check-mark in the "Bar" button.


Move using arrow key

When the problem is on your display you may click on any cell.

You can insert numbers in the light blue cell only. The light blue cell can be moved with the arrow keys (up, down, left, right).

The number you insert will appear in the light blue cell. When you insert a second number in a cell it will replace the number already there.

When you want to delete a number, enter "0" or press the "Delete" or "Back space" key.


Entering memo

When the check mark is in the "Memo" button you can put temporary numbers in the four corners of a cell with "Space-key" + "Number-key".


Notice: Shift key + Keypad keys (normally in the right side of the key board) cannot put temporary numbers.

The temporary numbers disappear from the screen when you put a number in a cell. When you delete the number, the temporary numbers re-appear.


Play using the mouse

Enable Bar

When you want to play using the mouse, insert a check-mark in the "Bar" button.


Select a cell by clicking on it and the "Number Bar" will appear. Click on the number you want in the "Number Bar", and your number will appear in the cell. When you click on another number, it will be written over the first number. When you want to delete the number in the cell, click the "Del" button in the "Number Bar".

With the check mark in the "Memo" button, a fan-shaped mark will appear in cell corners where the cursor is. Click on the mark and you can put a temporary number here.

Select a cell by clicking (the color turns light blue), you can insert numbers here via the keyboard.


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 number 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. Your first action is indicated as brown and the following yellow.


Cancel trying button

Click the "Delete" button in Try-mode, if you want to delete your trial actions. All your trial actions disappear and the point of your first action is indicated by yellow blinking corners.


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 black and you return to the solving-mode.