Samurai Sudoku (PuzzleMadness)

A Samurai Sudoku is five ordinary 9x9 sudokus joined into one: a grid in the middle, with four more grids each sharing one corner box with it. Every grid follows the normal rules, and the four shared boxes have to satisfy two grids at once. It is a long puzzle, closer to five sudokus than one.

The daily page opens today's puzzle on its own, and its title carries the date (on 3 October 2026 it read "Daily Medium Samurai Sudoku Puzzle for Saturday 3rd October 2026 (Medium)"). Each of Easy, Medium, Hard and Tough has its own dated grid. The Mixed page is a fifth grid, separate from the other four, and its level moves from day to day. On 28 October 2026 it was marked Hard but held a different puzzle from the Hard page. Past days stay in the archive, so a missed puzzle can be played later, and there is a print version and an image download of the grid. PuzzleMadness does not publish solutions: the site tells you when you have finished a grid correctly or made a mistake. Each completed puzzle adds to your total on the Samurai Sudoku monthly and all-time leaderboards, where only your best score on any one puzzle counts.

PuzzleMadness suggests working each of the five grids on its own at first, and only using the shared corners once you get stuck or near the end. The corner boxes are where a stalled grid usually gets unstuck, because a digit placed there counts in two grids. Set aside more time than for a single sudoku.

PuzzleMadness is a British puzzle site with dozens of daily puzzle types in the browser, from many sudoku variants to logic grids such as Nurikabe, Hashi and Slitherlink. It is free to play and carries ads. A free account keeps track of the puzzles you have finished and puts your name on the leaderboards, and the badges next to usernames mark how many puzzles a player has completed.