How to Get Better at Sudoku
Sudoku looks like a number puzzle, but it is really an elimination puzzle. These habits take you from slow and stuck to steady and confident.
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1. Scan before you fill
Take 20 seconds to look at the whole grid. The digits that already appear most often are the easiest to place next.
2. Use cross-hatching
Pick a digit. Cover the rows and columns that already contain it. In each box, only the uncovered cells remain, and often only one is left.
3. Count first in crowded units
A row, column or box with 7 or 8 digits filled is the fastest to finish. Check these first.
4. Use pencil marks only when you must
Note the possible digits in a cell once easy placements run out. Keep them small and update them each time you place a digit.
5. Learn naked pairs
If two cells in a unit can hold only the same two digits, those digits can be removed from the other cells in that unit.
6. Learn hidden singles
If a digit can go in only one cell of a row, column or box, it goes there, even if that cell has other candidates.
7. Check as you go
One wrong digit causes contradictions much later. If you get stuck suddenly, recheck your latest entries.
Frequently asked questions
- Do I need to guess in Sudoku?
- No. A well-made Sudoku can be solved by logic alone. If you feel you need a guess, look for a technique you have not tried yet.
- How long should an easy puzzle take?
- Most beginners take 10 to 20 minutes. With practice, easy puzzles often fall under 5 minutes.