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RULES & PRACTICE

How to Play Diagonal Sudoku

Play Diagonal Sudoku ↗

Game guide · GDFCWJ

Diagonal Sudoku: from controls to your first round

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. Keep the game area visible while you use its controls. Identify the playing area and the controls you need. Choose a clear next step rather than rushing through the instructions.

One thing to notice as you play

Read one step at a time and try it on the playing area. Match the instruction to the control you use. Use the example to check your reasoning.

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. The feedback beside the game helps you follow the round. Keep the controls in easy reach.

Follow these playing steps

  1. Select an empty cell. The original clues cannot be edited.
  2. Choose a symbol from the number pad, or type it on a keyboard.
  3. Turn Notes on to record candidate symbols without committing an answer.
  4. Use Check entries to check your filled values. Hint reveals one value from the verified solution.
  5. Complete the board, or choose New puzzle for another board.

Keyboard and screen 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. Read the example below alongside these instructions.

Work through an example

On one puzzle in this collection, row 1, column 1 has 1 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Focus on why the action is allowed, not only its outcome. Read the matching step again.

One detail worth checking

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Take a moment to reassess the position before continuing. 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

When I return, what is the goal of Diagonal Sudoku?

Here is the relevant explanation: 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.

For this browser game, how do I control Diagonal Sudoku?

Here is the relevant explanation: 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.

As a new player, what example helps explain Diagonal Sudoku?

Here is the relevant explanation: On one puzzle in this collection, row 1, column 1 has 1 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.

For my first round, what should I watch out for in Diagonal Sudoku?

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.

While reading the Guide, what format does Diagonal Sudoku offer?

The key detail is this: Play using the solo mode shown on this page. Read the controls before starting a new round.

Before I begin, which play mode does Diagonal Sudoku use?

The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.

For a quick reminder, where should I start with Diagonal Sudoku?

For clarity: Select an empty cell. The original clues cannot be edited.

For a quick reminder, 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.

How can I find Diagonal Sudoku again?

For clarity: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.

On this playing page, 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.

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