Alphabet Sudoku

Uses letters instead of numbers — and often spells a word in one row

What is Alphabet Sudoku?

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.

At a Glance

Constraint typeLetter Substitution
Typical givens24–32
Difficulty rating ★★☆☆☆ 2/5
Avg. solve time — Easy5 min
Avg. solve time — Medium12 min
Avg. solve time — Hard25 min
Avg. solve time — Expert45 min

How to Solve Alphabet Sudoku

TechniqueWhat it doesLevel
Same Logic, Different Symbols Every classic Sudoku technique applies — just with letters A–I instead of 1–9. Scanning, naked singles, and box interactions all work identically. Beginner
Letter-to-Number Mapping Internally, A=1, B=2, …, I=9. If numbers are more comfortable, mentally map each letter to its digit while solving. Beginner
Word Spotting Some Alphabet Sudoku puzzles are designed so a completed row or diagonal spells a recognisable word — identifying the target word can provide placement hints. Intermediate

Average Solve Times

Easy
5 min
Medium
12 min
Hard
25 min
Expert
45 min

Frequently Asked Questions

Which letters are used?
A, B, C, D, E, F, G, H, and I — the first nine letters of the alphabet, mapping to 1–9.
Is Alphabet Sudoku harder than Classic?
No — the difficulty is identical. Only the symbols change.
Can I type numbers instead of letters?
Yes — pressing 1–9 on the keyboard also works on our site.