Number Placement Puzzle

What You Actually Do

Every puzzle starts with a partially filled 9x9 grid. Some cells already hold numbers, and those clues are the only starting information you get. Your task is to fill the remaining empty cells with digits 1 through 9. The rule never changes: no digit may repeat in any row, any column, or any of the nine 3x3 sub-squares. A valid solution uses every digit exactly once in each of those groups.

Controls and the Highlighting Tool

Interaction is straightforward. You select a number from a panel at the bottom of the screen, then tap or click the cell where you want it placed. The game's most useful assist is automatic highlighting: when you pick a number, every instance of that number already on the board lights up. This makes it easy to see which rows, columns, and boxes are already blocked for that digit, so you can avoid an illegal placement before you make it. Mouse and touch input both work, which matters on tablets and phones.

Why the Format Still Works

Sudoku's appeal comes from the fact that the rules fit in a sentence while the solving process rarely does. Progress depends on elimination and pattern recognition rather than arithmetic. Early moves often come from rows, columns, or boxes that are already crowded with clues; later moves require tracking several constraints at once. There is no timer pressure described in this version, so the pace is entirely up to the player.

Platform and Presentation

This edition runs on HTML5, so it loads in modern browsers on desktop, laptop, tablet, and smartphone without extra plugins. Full-screen mode is supported, which removes browser clutter and keeps attention on the grid. The design is deliberately plain: no story, no avatars, no progression systems beyond the puzzles themselves. That restraint suits short sessions as well as longer, focused solving.

Compatibility