Fill the 9×9 grid so that each row, column, and 3×3 box contains the numbers 1-9 exactly once. Use logic — no guessing required!
Click a cell, then press 1-9 to place a number. N to toggle notes, Delete to erase. Arrow keys to navigate.
Start with rows/columns that have the most numbers filled. Use notes to track candidates. Eliminate possibilities one by one.