Alphabet / Word Sudoku
Uses letters instead of numbers — and often spells a word in one row
Alphabet / Word Sudoku is fully playable. Choose a difficulty and start solving.
Alphabet Sudoku (also called Word Sudoku or Letter Sudoku) uses a set of nine letters instead of digits 1–9. The rules are otherwise identical. Many Word Sudoku puzzles are designed so that a specific row, column, or diagonal spells out a word or name once solved. This makes the variant popular in newspapers and as a word-game crossover.
Like all Sudoku variants, Alphabet / Word Sudoku builds on the classic 9×9 foundation. Every row, column, and 3×3 box must contain each digit from 1 to 9 exactly once. The variant constraint is added on top of these standard rules, never replacing them.
If you're new to Sudoku, start by learning the basic rules and techniques before attempting variants.
Techniques Useful for This Variant
| Technique | How it applies |
|---|---|
| Pencil Marks / Notes | Essential for tracking candidates alongside the variant constraint |
| Obvious Singles | Cells narrowed to one candidate by the combined constraints |
| Hidden Singles | Digits with only one valid cell in a unit after variant elimination |
| Pairs and Triples | Locked candidates exposed by the additional constraint |