To enter a new puzzle click a cell and select a number for that cell.
Enter all the given numbers then click the "Start" button to begin
solving. To work on a sample puzzle select it from the list below.
To work on a puzzle click on a cell then use the yellow box to
add or remove candidates and the blue box to enter a value.
The colored buttons can be used to color cells to assist
solving. Use the "Undo" button to remove your previous changes.
If you want help to solve the puzzle click the "Next" button
and the helper will show you a next step.
Use the "Test" button to make sure the puzzle has a unique
solution.
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Load the numbers entered on the puzzle above and setup the puzzle for solving.Undo the last change to this puzzle.Clear this puzzle and start over.Test to determine if this puzzle has one and only one solution.Analyze this puzzle and show difficulty rating and strategies used to solve it.Create a new puzzle. If some solving strategies are disabled the new puzzle will require only the enabled strategies and Cross Hatching to solve and will present at least one instance of the most difficult enabled solving strategy even though it may not be required to solve the puzzle. If only one strategy is enabled that strategy will be needed somewhere in the path to solve the new puzzle.
To enter a new puzzle click on the cells to insert the given numbers then click "Start" to begin solving.
To have a puzzle created for you click "Create".
To work on a sample puzzle select one from the list.