Sudoku Strategies for Beginners

Start by scanning

Pick a number, say 5, and look at every 3 × 3 box that does not have a 5 yet. The 5s in other rows and columns rule out squares in that box. If only one square is left, the 5 goes there. Work through 1 to 9 like this and easy puzzles often fall apart.

Hidden singles

Scanning finds hidden singles: a number that has only one possible place in a row, column or box, even if that square could hold other numbers.

Naked singles

Now look at one square. Cross off every number already in its row, column and box. If only one number is left, it goes there.

Pairs

• Naked pair: two squares in the same row, column or box that can each only hold the same two numbers, say 3 and 8. Those numbers must go in those two squares, so remove 3 and 8 from every other square in that row, column or box.
• Pointing pair: if, inside a box, a number can only go in squares that lie in one row, it must be in that row within this box, so it cannot go anywhere else in that row.

Tips

• After placing a number, check its row, column and box again: one number often unlocks the next.
• Never guess. A proper Sudoku has one solution that logic alone can reach.
• A clash shows in red on our board, so a wrong number is easy to spot.

Try the techniques on today's puzzle in Sudoku, the same grid for everyone each day, or pick easy, medium or hard.