How to Play Hard 4x4 Sudoku

To solve Hard Sudoku 4x4, you must fill in the blank cells with the numbers 1 through 4, ensuring each digit only appears once in each row, column, or 2x2 block. It is a step up from Easy Sudoku 4x4 and suitable for kids in kindergarten and early elementary school. While the objectives of both levels are the same, the hard variation has fewer givens, or pre-filled numbers, making the puzzle more challenging to solve.

4x4 Hard Sudoku Techniques

In 4x4 Sudoku puzzles, you can use a couple of simple techniques to solve the grid:

• Scanning: Start by scanning the rows, columns, and 2x2 grids for missing numbers. When only one number is missing in a unit, you can fill it in with confidence.
• Counting: Count from 1 to 4 to identify which numbers in each unit are missing. Then, eliminate possibilities based on the numbers already placed in surrounding units.

Sudoku is a logic game with only one right answer, so before you fill in a cell you must be able to prove which number goes there. If you guess, that can cause a chain reaction of incorrect answers and make you start from square one.

Hard 4x4 Sudoku Example Solution

Now that you know the basic rules, let’s solve an example together!

1. Scan the puzzle, looking for units with only one missing answer. By doing this, you’ll quickly see that A1 is 1 (based on the row), C2 is 4 (based on the block), B3 is 2 (based on the block), and D4 is 4 (based on the row).
2. Scan the puzzle again, looking for new units with one missing answer. Because you added four answers to the grid, there are now only four blank cells. You notice that each column has three out of four numbers, so you can easily find the missing answers in each column. In this case A2 is 2, B2 is 3, C3 is 1, and D3 is 3.