Game guide · YALONGJS
A practical guide to Diagonal Sudoku
Make Diagonal Sudoku your next activity in the game library. 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. Use the example below to understand a decision.
One thing to notice as you play
Compare the worked example with your own position. Use the reasoning, not an answer copied from a different board. Refer to the controls when needed.
Aim for this result
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. Review the board or playing area as it changes.
A walkthrough of the rules
- 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.
One way to understand the rules
On one puzzle in this collection, row 1, column 1 has 2 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. 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. A different version of the game may use a different rule. Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart.
Questions about this game
What is the goal of Diagonal Sudoku?
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.
Before I begin, 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.
Before I begin, what example helps explain Diagonal Sudoku?
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.
As a new player, what should I watch out for in Diagonal Sudoku?
For clarity: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
For this browser game, what format does Diagonal Sudoku offer?
Play using the solo mode shown on this page. Read the controls before starting a new round.
On this playing page, 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 this browser game, where should I start with Diagonal Sudoku?
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?
Keep this in mind: No player account or payment is needed. Game scores are recreational results, not cash prizes.
For my first round, 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.
For a quick reminder, how do I report an issue with Diagonal Sudoku?
Keep this in mind: 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.