Sudoku Tips & Tricks

Diagonal sudoku adds one rule to the classic grid: both main diagonals must hold 1 through 9 exactly once. Here's how that changes solving, why the center cell matters most, and why X-Sudoku has nothing to do with the X-Wing technique.

Jigsaw sudoku keeps the row and column rules of classic sudoku but replaces the 3x3 boxes with nine irregular regions. Here is how to read those shapes, scan them correctly, and use the Law of Leftovers to crack the moves no other technique reaches.

The real evidence on sudoku and brain health: the 19,000-person PROTECT study, randomized trials, the skeptics' case, and what remains unproven. Every claim linked to its source.

Sudoku is one of the simplest brain games to play — but oddly one of the hardest to print well.If you've ever downloaded a Sudoku PDF only to find tiny...

Finding a genuinely good sudoku app is harder than it should be. Most of the top results are bloated with ads, push notifications, and in-app purchases that interrupt the puzzle...

Have you ever hit "the wall" in a difficult Sudoku puzzle? You've filled in all the "Naked Singles." You've scanned for "Hidden Pairs." But you're still stuck. The grid is...

The main sudoku techniques fall into three groups: scanning methods like naked and hidden singles that fill obvious cells, elimination methods like pairs and locked candidates that narrow down pencil...