Solving Daily Sudoku
This article explains how to play Daily Sudoku and details how you can solve it. The rules of the Sudoku game can be seen in the post The Sudoku Game, click here to go there. To play Daily Sudoku, click here.
Daily Sudoku game is a different game that we publish every day to all our users. It’s the same game for everyone.
This game has 21 visible cells and 60 hidden cells that must be discovered. The solution of the game is only one, and iterative solution techniques are not required to solve it. Here we will show you examples of how to solve them.
The Daily Sudoku game is a game for advanced level players, but on this website simple techniques are indicated to solve them. Beginner and intermediate players will be able to understand them easily.
Examples of our Daily Games
Every day the app initially displays the current day’s game. From there you can move to review previous days (from the last 2 months). The day and time valid in each part of the world corresponds to that of the place where you are playing.
Days on-line
On our website you will find available the games of every day of the current month until today, and all the games of the previous month. Future day games are not displayed.
The game for each day of the calendar is unique, you can return to that date whenever you want and you will always find the same game for each day.
Solutions
The solution of all Daily Sudoku games are available, except today’s game whose solution is shown from midnight. Midnight is measured in the place in the world where the player is playing. All Daily Sudoku Games have only one solution.
Level and Statistics
The Daily Sudoku game is a game for advanced users. It has 21 visible cells, 60 hidden. About 6 or 7 cells can be solved in the first step, all the rest in the next ones with the first solutions done.
It takes between 9 and 12 steps on average to solve this game.
In CrossGames21 about 20% of the players prefer this game, 15% of them finish it, and it takes about 15 minutes to do it.
Menu options
The menu options in the Daily Sudoku game are seven : Prev, Next, Guide, Pencil, Restart, Solve and Return.
The first option in the menu is Prev, which allows you to go back to previous days to see the games of those days. You can go back to the first day of the month before the current one.
The second option in the menu is Next, which allows you to advance to the next days to see the games of those days. You can go forward only up to the current day.
The third option on the menu is Guide. This option offers you some useful aids to solve the game.
The first is that when you select a cell on the board, the row, column and region numbers will be highlighted, so you can see which numbers you could put in that cell.
The second help of Guide is that when you select a number on the board, all the same numbers will be highlighted, so that you can see in which other cells it is possible to place that number.
Finally using Guide, the keyboard numbers that have already been filled in on the board will turn off, as shown below.
The fourth option on the menu is the Pencil. With this option you can write down in the empty cells, which numbers are candidates, based on which numbers are already placed in the respective rows, columns and regions. Below we show examples.
The fifth menu option is Restart, which allows you to restart the game. The system will ask you if you are sure because you will lose what you have advanced and you will not be able to go back.
The sixth menu option is Solve. With this option the system will show you the solution of the game. For the current day this option is not allowed (it will show you a message). The system will ask if you are sure you see the solution.
The last option is Return, which will return you to the main games menu. The system will ask you if you are sure because you will lose your progress and you will not be able to go back.
Solving cell by cell
To solve the game, we recommend different paths. The first two are with the Guide option from the menu.
Remember to put Guide mode on. The first and easiest trick to solve the game is the unique number to place in a cell. Look on the board for empty cells surrounded by many numbers. In some cases you will find that there is only one possible number left to put in that cell.
In the figure, the highlighted cell is surrounded by the numbers 1, 2, 3, 4, 5, 7, 8, and 9 in the same row, column, or region. So, it is only possible to put the number 6 in that cell.
You can repeat this search many times, and the more cells you fill, the greater the chance of finding new cells with a single solution.
The second way to use Guide mode is by selecting numbers from the board, which will highlight all the same numbers and allow you to identify cells that are the only option to place the same number.
The selected number is number 5. It is placed in regions 3, 4, 6 and 8. Highlighting the number 5 on the board, we can see that in region 5 and 7 there is a single cell that allows us to place the number 5, and after filling region 7, we see that in region 9 the same is true.
All these unique cells are shown with a blue box in the diagram, where we also show in light blue the 2 options to place the number 5 in regions 1 and 2.
Remember the numbering of regions on the right.
Solving with the pencil
Using the pencil, you can write in each cell all possible candidates for that cell.
This work can be done for a row, a column, a region, or for the entire board.
The first step in this technique is to select the pencil mode ON and place all the candidates in the empty cells (for the example, we did it in the whole board).
Finished, we will see some or many cells that have a single candidate. Consequently, for those cells, it is obvious that the solution is given.
Then, as seen in the diagram, the unique numbers already identified can be placed (in this case there are 5 cells).
Second step. After placing the unique numbers identified in the first step, we will have to repeat the process. In CrossGames21, when correct numbers are placed, the system discards candidates with the same number located in the same row, column, or region, giving rise to new cells with unique solutions.
Now we have in our example 6 new cells to place. In two steps the game advanced from 21 to 32 full cells.
The third step is the same. Now have 6 new cells to fill, making 38 in the game.
You can continue this process until you finish the game. You will see that for this example of the Thu, Nov 10, 2022, in the following stages it will find new unique cells : 6, 4, 2, 1, 3, 9, 6, 5 and 7. So in a total of 12 steps we can solve this Sudoku Daily Game. The advancing of visible cells for this day is : 21, 26, 32, 38, 44, 48, 50, 51, 54, 63, 69, 74 and finally the 81 cells.