Letter Sudoku

A normal Sudoku with a twist you can see at a glance: the starting numbers are arranged in the shape of a letter. Pick any letter from A to Z and its puzzle loads — the grid literally spells it out.

What is Letter Sudoku?

Letter Sudoku is an original spin on the classic puzzle. Instead of clues scattered at random, the given numbers trace the outline of a capital letter across the 9×9 board, so before you place a single digit you are looking at a big, friendly "A", "G" or "Z" made of numbers. Underneath that playful surface it is a completely ordinary, fair Sudoku: every board has exactly one solution reachable by logic alone, and you never have to guess. The letter is simply where the clues happen to sit.

How it works

The rules are the ones you already know. Fill every empty cell with a number from 1 to 9 so that each row, each column and each 3×3 box contains all nine numbers with none repeated. The cells that form the letter are highlighted and shown in full strength; a small number of fainter "helper" clues sit elsewhere on the grid. Those helpers are not decoration — they are there for a good reason. A letter shape on its own usually leaves whole regions of the board under-determined, which would allow more than one solution. The handful of faint helpers is the minimum needed to lock the puzzle down to a single, guess-free answer, so the letter stays the star while the maths stays honest.

Pick your letter

Above the board you will find the full alphabet, A to Z. Tap any letter and its puzzle appears instantly. Every letter is a genuinely different board with its own logic, and because thin letters give fewer clues than fat ones, the difficulty shifts a little from letter to letter — an "E" or an "O" tends to hand you more to work with than a slender "I" or "T". Switching letters never loses your place: each one keeps its own progress, so you can jump around and come back to any of them later.

A new set every day

Like our Daily Sudoku, Letter Sudoku is tied to the date. Each calendar day generates a brand-new puzzle for every letter, the same for everyone who visits, and at midnight the whole alphabet refreshes. That makes it perfect for a daily ritual and for a bit of friendly competition: because your "G" today is identical to your friend's "G" today, you can race the same board and compare times. The Share puzzle button copies a link to the exact letter and day you are playing, so sending someone your name — one letter at a time — is only a few taps away.

Spell something

The obvious game beyond a single letter is to spell a word. Solve the letters of your name in order, or set a friend a short word and see who finishes the set first. It turns a solo puzzle into something you can build a little challenge around, without changing anything about how Sudoku actually plays. However you use it, the tools you rely on elsewhere are all here: pencil notes, hints, undo and redo, a solve timer, automatic saving, and the site's light and dark themes.

Tips for your first letter

Treat a Letter Sudoku exactly as you would any board. Because the clues cluster along the letter's strokes, some rows, columns and boxes start out very full while others start nearly empty — so begin where the numbers are dense and let each placement feed the sparse areas. Keep your pencil notes tidy, and remember the faint helper clues count just like any other given. Start with a rounded, clue-rich letter such as "O", "G" or "S" to get the feel, then work toward the leaner ones. When you want the classic experience back, the standard board is always waiting at Sudoku AZ, and the Daily gives you one shared puzzle a day.