Our Hard level online sudoku puzzles: On SudokuLovers.com you Can play high-quality Hard level web Sudoku, The difficult Puzzles are daily curated and are forever free! We also have a daily challenge so you can keep your mind sharp! Easy Medium Hard Evil. Today's Variation JigSawDoku. Each Sudoku has a unique solution that can be reached logically without guessing. Enter digits from 1 to 9 into the blank spaces. Every row must contain one of each digit. So must every column, as must every 3x3 square. Play Offline with Web Sudoku Deluxe. Download for Windows or Mac OS X.

SUDOKU RULES

Sudoku is a puzzle game, where the object is to use the numbers from 1-9 to fill every row, column and box. Each number can only occur once in every row, column or box. A number of fields will have numbers in them at the start, the rest will be filled in by you. If you manage to fill all the fields without ever having a duplicate number in a unit (row, column or box), you win the game.

SUDOKU STRATEGY

There are a number of complicated strategies you can use to figure out the right numbers. The most basic one is of course to just look at a single row, column or unit and see if there is any field where there's only one possibility. Each field is a part of one row, one column and one box. So, if you're looking at a field and see that in its row you have 1,2,3, in its column you have 4,5,6 and in its box you have 7,8, then you know that only 9 can fit in that box, since any other number would create duplicates in one of its units.

Of course there are also many other strategies to use, but we won't go into them here. Couple of useful things to know:

• You can put multiple numbers in a field, for example if you know it might be 1 or 3, it might be useful to put both of those in there. To do that, press the button that shows multiple numbers, once that's down you can enter multiple numbers. Even if it's not down you can always hold down Shift on your keyboard while clicking on the number you want, then you will always put a small number in.
• If you have lots of numbers in one field, but you've found out the one number you want, you can select the field, press the number key on your keyboard and just hold it down for about a second, and the one number will replace all the small ones. In fact my favorite way to play is to just leave the multiple numbers option on at all times, and when I'm sure about a number just hold it a little longer to put it in. Makes it easier, not having to constantly switch to and from multi number mode!
• Click on the lightbulb to get a hint if you're having problems.
• Click on New Game to start a new game. You will be asked whether you want an easy sudoku puzzle, medium sudoku puzzle or a hard sudoku puzzle. The difference is the number of pre-filled fields at the start.
• Click on the Keyboard button if you're playing on a desktop computer and want to use your keyboard and don't like seeing the number buttons.

PRINT SUDOKU PUZZLES

You can always print the puzzle currently on screen, doesn't matter if it's partially filled in, just hit the Print button in your browser and you'll get a clean printout of only the puzzle without anything filled in, and without any of the extra webpage text. Just try it!

ABOUT

Sudokuu.com is made by the CardGames.io team. We already have a Sudoku game on our main site but figured it would be nice to have a special site only for Sudoku. If you're on a phone we highly recommend adding a shortcut to the game to your homescreen, that will let you start up in full screen mode, and will feel almost exactly like an app.

This is version 104 of Sudokuu.com

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Initially activate the 'Auto' option for converting single digit pencil marks into regular entries (only for initial setting, not changing the current mode).

Automatically check if the puzzle is correctly solved.

Show numbers of digits yet to be filled.

When highlighting all related cells, highlights follow your cursor movements. (Otherwise follow your clicks.)

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Sudoku

Sudoku is a logic puzzle game. The objective is to fill the 9x9 Sudoku grid with digits 1 to 9 such that each of these 9 digits appears in each row, each column and each 3x3 sub-grid once any only once.

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Play our billions of Sudoku puzzles on your mobile devices such as tablets and smartphones. If you have a large screen phone, try both versions to see which one is a better fit for your device. We also encourage those mouse-only PC players to try our Sudoku Mobile page that has a 'Cell First' option for entering multiple pencil marks in one cell at a time.

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Our new smart solver not only gives the solution for a puzzle, but also explains every step with demonstrations in the grid. You may learn Sudoku solving techniques through examples with numerous puzzles from our database. Try Smart Solver now.