What is Sudoku?

  • Sudoku is a puzzle game designed for a single player, such like a crossword puzzle. The puzzle itself is a grid of 81 fields stacked in 9 rows and 9 columns.
  • The goal of the puzzle is to fill
    • each 3x3 block,
    • each column and
    • each row
    with the numbers 1 through 9.
  • A number must not be repeated twice within the same 3 x 3 block, same cloumn as well not within the same row.
sudoku objective
  • The word Sudoku actually comes from a Japanese phrase containing the words "Su" and "Doku", which means "the numbers must be single".
  • Sudoku is not a math game, but is rather about identifying logical patterns.
  • In fact, Sudoku doesn't really involve numbers at all. The fields in the puzzle could also be filled with nine letters of the alphabet, nine different pictures, or even nine colors! Numbers are only used because they are well-recognized symbols.
  • For more info have a look at wikipedia

Sudoku Game

  • The numbers are generated randomly. Depending on the degree of difficulty, some of the numbers (usally half) are not displayed.
  • Sudoku puzzles vary in difficulty from simple to very difficult. The fewer numbers displayed, the heavier the level.
sudoku gameboard
  • The goal is to fill the empty fields of the Sudoku puzzle based on the existing numbers.
  • Complex strategies must be utilized in order to solve the hardest puzzles.
  • Guessing is rarely necessary to solve the game.
  • The puzzle have often unique solution that can be arrived at using pure logic.
  • Depending on the constellation of the 'given' numbers, Sudoku may
    • have 1 or many solutions or
    • even not be fully solved
  • The game is completed, once (if possible) all empty fields are filled.

Brain Jogging:

We like to keep our bodies active, but why don't we invest the same amount of care in our minds? Research shows that variation in our mental activity is the key to long-term success.
  • Sudoku improves your memory. Memory and logic work side-by-side when you are playing Sudoku. We use our memory to memorize the numbers, when we use our logic to figure out the next empty field.
  • Sudoku stimulates your mind. It keeps you practicing your logical thinking process when you are solving a puzzle, and eventually improve your number skills.
  • Sudoku reduces the chances of developing Alzheimers by keeping your brain active.
  • Sudoku leads to learn to do things quickly. Not only playing Sudoku is interesting but it helps to increase your sense of time. You will learn how to make a decision and take an action with less hesitation.
  • Sudoku increases your concentration power. Sudoku requires players to think strategically and solve problems creatively. Once you stop playing in the middle of the game, you have to start the whole thinking process, which helps you to develop your concentration power and re-focus skills.
  • Sudoku makes you happy. Sudoku gives you a sense of accomplishment when you can solve a puzzle, especially the puzzle is a difficult one.
By playing Sudoku more often, you can solve the puzzle faster and eventually advance to a harder level. Exercise your mind and you will become happier and smarter. From now on, spare a little time to play Sudoku every day here at
sudoku-prime.com 🙂


There are different strategies to find-out a missing value. Feel free to contact me if you have other strategies than listed below.

Strategy 1:

The solution for the next [?] marked field is 1, because other empty fields of the outlined 3 x 3 block are already excluded through row 1 and 3, and column 7.
sudoku strategy 1

Strategy 2:

The solution for the next [?] marked field is 9, because only 9 is missing in the outlined 3 x 3 block.
sudoku strategy 2

Strategy 3:

The solution for the next [?] marked field is 3, because
  • missing values in row 4 are 3,4,6
  • number 3 can not be used for both missing values in the outlined 3 x 3 block
sudoku strategy 3

Strategy 4:

The solution for the next [?] marked field is 6, because numbers 1-5 and 7-9 are already excluded.
sudoku strategy 3

Strategy 5:

The solution for the next [?] marked field is 2, because other 3 empty fields of the 3 x 3 block can not contain 2.
sudoku strategy 5

Strategy 6:

The solution for the next [?] marked field is 1, because
  • looking at column 4 shows fields where number 1 can not be placed
  • looking at column 5 shows fields where number 1 could be placed
sudoku strategy 6a
  • looking at the red outlined 3 x 3 block below shows where number 1 can also not be placed.
Finally the initial [?] marked field must be 1.
sudoku strategy 6b

Strategy 7:

The solution for the next [?] marked field is 5. Let's find the solution step by step.

The missing values in the red outlined 3 x 3 box are 4, 5, 6, 8, 9.
sudoku strategy 7a
Looking below at column 1 and 2, and last row, we can
  • exclude 4 and 8 from the red marked fields and
  • conclude 4 and 8 must be therefore in the blue fields
sudoku strategy 7b
Now looking below at column 1 again, we can
  • exclude 5 also from the red marked fields and
  • conclude 6 and 9 must be (instead) in the blue fields
Finally the initial [?] marked field must be 5.
sudoku strategy 7c
This website is using cookies from Google Analytics for reporting purpose. For more info please read the Disclaimer. I confirm!