Game guide · FJZHENSEN
A practical guide to Diagonal Sudoku
Diagonal Sudoku gives you a focused activity to play in your browser. 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. Look at what changes after your first action. Identify the playing area and the controls you need. Use the example below to understand a decision.
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. Make the next step deliberately.
What the game asks you to do
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. Try to explain the aim in your own words.
Work through the instructions
- 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.
The controls to know
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. Look at the feedback after the action.
Try this example
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. Apply the same reasoning to the position in your own round. Choose a deliberate next step.
Keep this in mind
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. Watch the feedback after an action. A message can explain whether the input was accepted or whether a rule needs attention.
Common questions
For this browser game, what is the goal of Diagonal Sudoku?
Keep this in mind: 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?
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.
For my first round, what example helps explain Diagonal Sudoku?
Keep this in mind: 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.
While reading the Guide, 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.
When I return, 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.
For this browser game, 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.
For my first round, where should I start with Diagonal Sudoku?
Here is the relevant explanation: 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?
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 learning, 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.