Game guide · ZHJW-TNY
Diagonal Sudoku: rules and examples
Open Diagonal Sudoku, check the instructions and begin a round. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once. Check the relevant rule before repeating a move. Identify the playing area and the controls you need. Keep the game area visible while you use its controls.
A small practice goal
Before your first action, say what you are trying to achieve. Then compare the result with the goal. Refer to the controls when needed.
What counts as success
Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once. The feedback beside the game helps you follow the round. Take a moment to understand the current position.
Follow these playing steps
- Select an empty cell. The original clues cannot be edited.
- Choose a symbol from the number pad, or type it on a keyboard.
- Turn Notes on to record candidate symbols without committing an answer.
- Use Check entries to check your filled values. Hint reveals one value from the verified solution.
- Complete the board, or choose New puzzle for another board.
How to use the controls
Tap or click a cell and use the number pad. Keyboard: arrows select cells; digits (and A–G on 16×16) enter values; Backspace erases. Read a button’s label before selecting it. Avoid pressing the same control repeatedly while a move is being processed.
See how the rules apply
On one puzzle in this collection, row 1, column 3 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Use the example as a guide rather than a substitute for reading your board. Verify the rule before continuing.
Where a round can go wrong
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Compare the situation with the worked example. When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round.
Common questions
Before I begin, what is the goal of Diagonal Sudoku?
The key detail is this: Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The two long diagonals must also contain each symbol once.
How do I control Diagonal Sudoku?
For clarity: Tap or click a cell and use the number pad. Keyboard: arrows select cells; digits (and A–G on 16×16) enter values; Backspace erases.
For this browser game, what example helps explain Diagonal Sudoku?
Keep this in mind: Before filling a cell, compare the symbols already used in its row, column and 3 × 3 region. A candidate must be absent from all three. The two long diagonals must also contain each symbol once.
As a new player, what should I watch out for in Diagonal Sudoku?
The key detail is this: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
When I return, what format does Diagonal Sudoku offer?
Play using the solo mode shown on this page. Read the controls before starting a new round.
For a quick reminder, which play mode does Diagonal Sudoku use?
The key detail is this: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
While reading the Guide, where should I start with Diagonal Sudoku?
Keep this in mind: Select an empty cell. The original clues cannot be edited.
Before I begin, do I need an account or a payment for Diagonal Sudoku?
Here is the relevant explanation: No player account or payment is needed. Game scores are recreational results, not cash prizes.
For this browser game, how can I find Diagonal Sudoku again?
Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
While reading the Guide, how do I report an issue with Diagonal Sudoku?
The key detail is this: Use the contact form and include the game name, browser, device and the actions that led to the issue. Do not send passwords or payment details.
