WHICH DIGIT FITS THE CELL?

Sudoku Unlimited begins with a 9x9 grid divided into nine 3x3 boxes, with some digits already in place. Fill every remaining cell so that each row, column, and box contains the digits 1 through 9 exactly once. A digit cannot be repeated within any of these three groups, so each entry must follow the information already on the board.

Tap or click a cell, then enter a digit to place an answer. Switch on Notes, or hold Shift while entering a digit, to add a pencil mark instead. Arrow keys move between cells, while Backspace or Delete removes an entry. Press Space or N to switch pencil mode, H to request a hint, and U or Ctrl+Z to undo a move.

Choose a Board and Difficulty

Sudoku Unlimited includes six difficulty levels based on the techniques needed to solve a board. Fast uses scanning only, while Easy focuses on singles. Medium introduces pairs and box or line reductions, while Hard requires these methods more often. Expert mode uses patterns such as X-Wings, Y-Wings, and simple colouring. Evil adds chains and may require a hint.

Daily mode provides one board at each difficulty every day and records a streak. Unlimited mode generates a new board whenever needed. An archive also keeps past daily boards available by date and difficulty.

ONE SOLUTION THROUGH LOGIC

Every Sudoku Unlimited board has exactly one answer and is checked so it can be completed through deduction. The number pad can show how many copies of each digit remain, while optional shading identifies cells connected to the selected space. Hints name the pattern they find before explaining the deduction and making a move.

Work through a board in Sudoku Unlimited by narrowing each row, column, and box one digit at a time.