Game guide · SQXQKJ
Learn the rules of Diagonal Sudoku
Try Diagonal Sudoku at your own pace and keep its objective in view. 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. Choose a clear next step rather than rushing through the instructions. Identify the playing area and the controls you need. Keep the game area visible while you use its controls.
Build familiarity through play
Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart. Keep the objective visible.
Your objective
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. Use the instructions to see which actions move you towards it. Start with a deliberate move.
The order of play
- 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.
Choosing and moving on screen
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. Keep the playing area visible while using these controls. A new-round button replaces the current round.
Learn from a sample situation
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. Focus on why the action is allowed, not only its outcome. Notice the change in the playing area.
A mistake to avoid
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Check the rule before repeating the action. Choose one rule to keep in mind for this round. Apply it consistently rather than guessing what another version might allow.
Read these answers for extra help
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.
On this playing page, how do I control Diagonal Sudoku?
The key detail is this: 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.
On this playing page, what example helps explain Diagonal Sudoku?
Here is the relevant explanation: On one puzzle in this collection, row 1, column 5 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
For this browser game, 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?
For clarity: Play using the solo mode shown on this page. Read the controls before starting a new round.
Which play mode does Diagonal Sudoku use?
Keep this in mind: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
For my first round, where should I start with Diagonal Sudoku?
Keep this in mind: Select an empty cell. The original clues cannot be edited.
For my first round, do I need an account or a payment for Diagonal Sudoku?
The key detail is this: No player account or payment is needed. Game scores are recreational results, not cash prizes.
While learning, 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.
When I return, how do I report an issue with Diagonal Sudoku?
Here is the relevant explanation: 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.