Naked Single Technique is the simplest technique in Candidates Elimination Techniques. To use this technique, what you have to do is just to scan the possible-candidates grid to search for a cell which has a sole candidate only. If such a cell is found, what you have to do next is to fill in the cell with this candidate number and remove this candidate from the cells in the column, row and block where this cell lies.

In the example below:

There is a sole candidate 1 at cell [I1], so we fill the cell with value 1 and eliminate all 1s in its related column, row and block:

Now the current possible-candidates grid looks like this:

Although Naked Single Technique is very simple, it is also the most effective technique. Especially when the puzzles are very easy, you can solve them by continuously applying this technique only.

See Also:

• What is Sudoku: rules, history and terminology
• Sudoku Strategies
• Direct Elimination Techniques
• Candidates Elimination Techniques
• --> Hidden Single Technique
• --> Intersection Removal Technique
• --> Naked Pair Technique
• --> Naked Triplet Technique
• --> Naked Quad Technique
• --> Hidden Pair Technique
• --> Hidden Triplet Technique
• --> Hidden Quad Technique
• --> X-Wing Technique
• --> XY-Wing Technique
• --> XYZ-Wing Technique
• --> Swordfish Technique
• --> WXYZ-Wing Technique