Top 10 Sudoku Solving Tips

Let's begin with the most obvious. Understanding the rules is the key to solving Sudoku puzzles. The objective is to fill in numbers in the empty squares so that each row, column, and 3x3 grid contains each of the numbers 1-9. Each number can only appear once.

Sudoku is a game of logic and reason, these rules will help you to determine, through a process of elimination, which numbers go in each square.

Another simple, yet useful tip. A well written Sudoku puzzle, regardless of difficulty, should always be solvable without the need for guessing. Logic and deductive reasoning is all that should be needed. If you need to guess, move on.

This might seem obvious, however, many new Sudoku players immediately jump into the hardest puzzle they can find, and then get frustrated when they can't solve the puzzle. Start with simple, easy puzzles, and work your way up.

Many Sudoku web sites and publications focus on completing the puzzle as quickly as possible. When you are first learning Sudoku, focusing on solving the puzzle quickly can lead you into trouble. Until you gain some experience, take your time, the goal should be to complete the puzzle correctly, not quickly.

Givens are the numbers in a Sudoku puzzle that have already been filled in. Givens, are given for a reason. They provide the initial clues to help you begin filling in the puzzle. Using the givens and simple techniques like Cutting/Scanning at the beginning of a puzzle can really begin to fill out the empty squares. Start working your way from left to right and top to bottom, find a given and scan for any empty squares that can be filled in using that number.

The first mistake most new Sudoku players make is entering a number without being 100% sure. As you progress through the puzzle, you will eventually make decisions and enter numbers based on previous entries. If these entries are incorrect, the entire puzzle can be ruined and must be started over. It is therefore key to ensure that all entries are correct. The easiest way to ensure this is to begin by entering numbers that can be determined using the givens alone. Use Cutting/Scanning and/or Last Number Standing/Candidate Elimination with the givens to enter "definite" values.

Once you have filled in a number into one of the squares (and you're sure that's where it goes), immediately use the Cutting/Scanning technique to fill in any additional numbers that can be deduced from that number. This helps to ensure that any easy and obvious numbers don't get lost in the shuffle.

Most Sudoku puzzles rated "hard" or above can rarely be solved using Cutting/Scanning or other simple techniques alone. It is usually possible to only fill in one or two numbers during the early stages of the puzzle. Using the Last Number Standing/Candidate Elimination technique is usually the only way to really begin to enter values.

A common mistake beginner Sudoku puzzle players make (especially when feeling stuck), is to aimlessly wander the puzzle looking for a value to fill in. This wastes time and is very unproductive. Work your way left to right and top to bottom, start with the givens and then the numbers you have filled in, cutting/scanning for numbers that can be entered. Be sure to check both rows and columns.

As with anything in life, practice makes perfect. As you begin to play more Sudoku puzzles, the above tips will become second nature. To gain experience Play Sudoku Online or print off Printable Sudoku Puzzles. The more you play, the better you will get!