THE PLAYBOOK · QTHCC
How to play 16x16 Sudoku
Start 16x16 Sudoku in your browser at QTHCC. Fill all cells with 1–9 and A–G; do not repeat a symbol in any row, column or region. The page pairs the game with observe, then act, an example and answers about this edition.
Observe, then act
Look at the full play area and read the status message. Make a deliberate choice and compare the outcome with your expectation.
Your goal
Fill all cells with 1–9 and A–G; do not repeat a symbol in any row, column or region.
Step by step
- 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.
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.
A useful example
Before filling a cell, compare the symbols already used in its row, column and 4 × 4 region. A candidate must be absent from all three.
Watch out for this
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
Common questions
What is included in this edition?
A real 16 × 16 puzzle with 4 × 4 regions, candidate notes, undo and saved progress. Every included puzzle is checked for a unique solution.
Which controls should I use?
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.
Can you show a concrete example?
Before filling a cell, compare the symbols already used in its row, column and 4 × 4 region. A candidate must be absent from all three.
