Logic puzzles that reward patience, not luck — Sudoku variants, number-cages, region-shading and bridge-building, all free in your browser.
Every puzzle on this page is a true logic puzzle — one solution, always reachable by reasoning rather than guesswork. That single rule ties together puzzles that otherwise feel nothing alike.
You place numbers under constraints in Variant Sudoku and Suguru, work arithmetic cages in Calcudoku and Kakuro, shade islands in Nurikabe, or connect them up in Hashi. Each rewards a different habit of mind.
Grids scale from a quick 5×5 to a meaty 11×11 across seven levels — from Beginner, which leaves a few helping hints on the board, up to Cyborg, which leaves you nothing but the logic.