Sudoku #1271037

Pencil Marks 

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Sudoku Hard

This level of difficulty demands concentration and patience. You need to have some tools in your belt to solve this one and actually enjoy while doing so. What an inexperienced player would think is brain busting impossible sudoku, You might consider a good bone stretch.

Either way, let us run you through some tips and tricks.

How to solve hard sudoku - sudoku tricks

What makes hard sudoku is the scarcity of the originally given numbers, which makes you need to use pencil marks, go through the numbers in your head and use your memory.

Still, there are patterns that you can utilize that are powerful solving techniques we are sure you would appreciate.

Sudoku X-wing

look for 4 cells with the possible same digit that create the shape of an X. See image below: A sudoku grid filled with pencil marks with 4 cells focused on creating the shape of X. Go to the x-wing tutorial

Sudoku swordfish

The same principle of the x-wing method only this time isolate 3 columns with the same possible digit. See image below: Three rows highlighted in a sudoku grid marked with pencil marks on livesudoku. Go to the swordfish tutorial

The LiveSudoku game features

If you are a frequent user here you probably know the great ease in which the game is set in our sudoku kingdom.

For you the new visitor, a great feature we have is called highlight digit, which highlights the digit you want across the whole grid, making it very eye-friendly to spot that eluding empty cell.

For the advanced sudoku games, you can use the pencil mark which lets you type in more than one optional digit in a specific cell, allowing you to narrow down all the optional numbers.

There is also an undo button which is so useful. You can check yourself at any time with the check solution button.
You can press the options button and tweak your preferences of some colors and our help level. So start playing web sudoku easy level and have fun!

About live sudoku

Live-Sudoku was created in 2006 and is one of the original websudoku sites. The creator of the website Mr. Izenberg built it with the same love he has for the game. LiveSudoku is home to all Sudoku players around the world from easy and medium sudokus to hard and evil sudoku levels.

You can invite a fellow Sudokuer for a match of speed and concentration. Sign in to track your statistics, see your best and worst games and compete in the arena of sudoku enthusiasts. Enjoy your game!

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Arrow keysMove the cursor around the Sudoku grid
1-9Fill digit in cell
TabMove to the right
Shift + TabMove to the left
BackspaceClear cell
SpacebarClear cell
DeleteClear cell
Ctrl + ZUndo move
EraseClear all digits from the Sudoku grid
CCheck solution
Ctrl + SSave game
ALT + 1-9Highlight Digit
The following keys require that "Allow pencil marks" is enabled from the options menu:
VClear all pencil marks
1-9When digit already present in cell - make the digit a pencil mark
1-9When digit is a pencil mark - remove the pencil mark
0 or H or EnterFill pencil marks automatically

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Hard Puzzle #1271037
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Hard Puzzle #1271037

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