Good news, the 3is2much puzzel is back.

Fill in your daily Sudoku

Medium     Hard

You can fill in the puzzle online, in the same way, as working on a printed version. Just click on a square to fill in the number. When more then one number is entered, the numbers become pencil marks (candidates). You can also use the arrow-keys to select a neighbour field.

Click the number on the left to toggle the highlighting of a number on and off. When a number is highlighted, use the Shift-click on a field to enter this number, or Ctrl-Shift-click to remove the number of the candidates (pencil marks). To restore the previous setting, do a Shift-click or Ctrl-Shift-click once again.

For entering the coloring mode, just Alt-click on a field to change its color. With a first Alt-click, the color is changed to green, a second Alt-click changes the color to blue, and a third Alt-click removes the color. The coloring mode can be reseted by clicking a number on the left.

There are four levels of difficulty and various techniques are potentially required to solve each level, however, any particular Sudoku doesn't necessarily require all possible techniques for that level. The difficulty level is also very tricky to gauge, as one person may find certain techniques easier than others. Almost certainly the hardest of one level will be harder than the easiest of the next level up, so there is a certain amount of crossover between the levels. Of course techniques needed for a higher level, can be used to find a solution for a lower level, but there is always a way to find a solution without the use of this higher level techniques.

Single Candidates
Single Unit Candidates 
Naked Pairs 
Disjoint Subsets  
Simple Coloring   
Unique Rectangles   

All Sudokus are designed to be solved with the indicated techniques, no other techniques are needed.

Take your Sudoku, with you, on a holiday.