--- title: "Wordoku: Sudoku with Letters, Not Numbers | Sudoku Flow" description: "Wordoku is Sudoku with nine letters instead of digits, often from a word that appears once solved. The rules, a puzzle to try, and how to solve it." url: https://sudokuflow.com/guides/wordoku-letter-sudoku/ language: en last_modified: 2026-11-06 --- [Sudoku guides](https://sudokuflow.com/guides/) # Wordoku: Sudoku with Letters Instead of Numbers Wordoku is Sudoku with nine letters instead of digits, often from a word that appears once solved. The rules, a puzzle to try, and how to solve it. Updated 2026-11-06 ## Quick answer Wordoku is Sudoku with nine letters in place of the digits 1 to 9. The rules do not change: every row, column and box holds each letter once. The letters usually come from a nine-letter word with no repeated letter, and in many puzzles that word appears in a row, column or diagonal once the grid is solved. Any Sudoku can be turned into a Wordoku, so it is solved exactly the same way. - Nine letters take the place of the digits 1 to 9. - Every row, column and box holds each letter once. - The letters often spell a word with no repeated letter. - In many puzzles the word appears once the grid is solved. - It is solved exactly like a Sudoku with numbers. ## The rules Fill the grid so that every row, every column and every 3×3 box holds each of the nine letters exactly once. As in any Sudoku, a good puzzle has exactly one answer. The letters are only symbols: their order in the alphabet means nothing. ## A Wordoku to try This is the second Easy puzzle from our printable sheets, with each digit turned into a letter of the English word FARMHOUSE. The letters were matched so that the word reads across the top row of the answer. It has 51 letters given and exactly one answer. ```text F . R | M . O | U S E M . O | . E S | . . . U S E | A . R | M . . ------+-------+------ A . . | . M U | O . H O M U | H R . | A . S H . S | O . F | . M U ------+-------+------ R . . | . . . | S . M S O . | F . M | E R A E U . | . S . | H O F ``` *A Wordoku from our second Easy puzzle: the letters of FARMHOUSE, which reads across the top row once solved.* ## How to solve it - Write the nine letters where you can see them, so you know which ones a row or box is missing. - Look for squares with only one letter left, and letters with only one place left in a row, column or box, just as with digits. - Some solvers turn the letters back into numbers first; it works because only the pattern matters. - The hidden word is a bonus, not a rule: never place a letter just because it would complete the word. [Is Sudoku Math? 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We also make a Sudoku app for iPhone, iPad, Mac and Android. There are no ads in it at all, it works offline, and when you ask for a hint it shows you the technique instead of just filling in a number. [App Store iPhone, iPad, Mac](https://apps.apple.com/app/apple-store/id6502922368?pt=125379530&ct=sudokuflow_web&mt=8) [Google Play Android](https://play.google.com/store/apps/details?id=com.rubigogames.sudoku&referrer=utm_source%3Dsudokuflow%26utm_medium%3Dweb%26utm_campaign%3Dsite) Sudoku Flow is made by Rubigo Games, the developer of the Sudoku app recommended on this site.