READ THE SIGNALS
Fill every row, column and outlined box without repeating a digit.
Choose a cellTap it or move with the arrow keys.
Place or noteUse the number pad or keys 1–9.
Complete the gridEach unit needs every digit exactly once.
Choose a cell, then place a digit.
Game guide · Logic puzzle
Limegrid Sudoku is a focused number-placement puzzle with three genuinely different board sizes. Read the fixed clues, rule out impossible positions and complete a grid that always has exactly one solution.
Fill every empty square so each row, each column and each outlined box contains every digit exactly once. Easy uses digits 1–4 in a 4 × 4 grid, Medium uses 1–6 in a 6 × 6 grid, and Hard uses the classic digits 1–9 in a 9 × 9 grid. Fixed clues cannot be changed.
Select a cell by tapping, clicking or using the arrow keys. Enter a number with the on-screen pad or keyboard. Notes mode stores several small candidate digits, Erase clears your entry, Check marks current mistakes with an icon, and Hint reveals one correct digit when you need a nudge.
The Daily button recreates the same puzzle for everyone on the same UTC date and difficulty. New puzzle generates another uniquely solvable board. The timer pauses when the tab is hidden, and your best clean solve for each difficulty is kept locally when browser storage is available.