Sudoku Types

The classic 9×9 sudoku you see in most newspapers is just one variant in a family that spans dozens of related puzzles. They all share the basic logic — fill in numbers so that certain groups contain no repeats — but the constraints and shapes vary enough that experienced solvers find themselves picking up new vocabulary for each. Mini sudoku (6×6) uses the digits 1–6 in a grid divided into six 2×3 boxes. It's the natural step up from 4×4 kids sudoku and a friendly entry point for new solvers. Kids sudoku (4×4) uses just the numbers 1–4 in four 2×2 boxes and is the gentlest possible introduction. Both share classic sudoku's rules; the smaller grids just take less time per puzzle. Killer sudoku is the most popular variant after classic. The 9×9 grid ships completely empty — no givens — but cells are grouped into outlined cages, each carrying a target sum. Standard row/column/box rules still apply, plus digits inside a cage must be unique and add up to the cage's sum. The result is a puzzle that feels like a logic puzzle and an arithmetic puzzle fused together, and the cage combinations open up entirely new techniques like the 45-rule and innies/outies. Other widespread variants include jigsaw sudoku (the boxes are irregularly shaped instead of 3×3), hyper sudoku (extra constraint boxes overlap the standard ones), and X-sudoku (the two diagonals also must contain 1–9). Samurai sudoku stacks five overlapping 9×9 grids into a single mega-puzzle. The New York Times Crossword sudoku is classic 9×9 with their own difficulty calibration. Our supported variants today are classic 9×9 (at all difficulty tiers), 6×6 mini, 4×4 kids, and killer 9×9 (easy through expert). The articles in this category cover the rules and the appeal of each major variant, what makes each distinctive logically, and which variant suits which kind of solver. If you're comfortable with classic sudoku and looking for the next step, this is the place to find it.