# Types of Sudoku Explained: Killer, Jigsaw, Mini, X and More

**Quick answer:** Beyond classic 9x9 Sudoku, the most popular variants are **killer** (cages with sums), **jigsaw** (irregular regions), **mini** (4x4 or 6x6), **X-Sudoku** (diagonals must also hold 1–9), **hyper** (extra inner boxes), and **samurai** (five overlapping grids). They all keep one idea: no number repeats within a defined group.

If you have mastered the [classic 9x9 grid](/guides/how-to-play-sudoku), you have probably wondered what the "killer" or "jigsaw" labels on other puzzles mean. Here is a plain-English tour of the family — and one puzzle that is often confused with it.

## Classic Sudoku

The original and by far the most common. A 9x9 grid split into nine 3x3 boxes; fill it so every row, column, and box holds 1–9 exactly once. Everything below is a twist on this foundation. You can [play classic Sudoku free here](/) in easy, medium, hard, or evil.

## Killer Sudoku

Killer Sudoku adds a dash of arithmetic. The grid is carved into dashed-outline **cages**, each labelled with a target sum. The digits in a cage must add up to that number **and** never repeat inside the cage — on top of all the usual row, column, and box rules. Because many cells start empty, cage sums become your first foothold. It's the most popular variant after the classic, and it's a built-in mode in the Sudoku Aura app. New to it? Read our [full Killer Sudoku guide](/guides/killer-sudoku-how-to-play).

## Jigsaw Sudoku

Also called **irregular** or **squiggly** Sudoku. The nine neat 3x3 boxes are replaced by nine irregular, interlocking shapes. The rules are otherwise identical: 1–9 once per row, per column, and per jigsaw region. The odd shapes break the visual habits you build on classic grids, which makes jigsaw feel surprisingly fresh.

## Mini Sudoku (4x4 and 6x6)

Smaller grids for a quicker solve. A **4x4** uses digits 1–4 in four 2x2 boxes; a **6x6** uses 1–6 in 2x3 boxes. With less to track, mini Sudoku is the friendliest entry point for kids and newcomers — and a fast coffee-break option for everyone else. You can [print free 4x4 kids puzzles](/print/kids) and [6x6 puzzles](/print/6x6), or play them in the Sudoku Aura app. See our [Sudoku for Kids guide](/guides/sudoku-for-kids) for how to get children started.

## X-Sudoku (Diagonal Sudoku)

A classic 9x9 grid with one extra rule: each of the two **main diagonals** must also contain 1–9 exactly once. Those diagonals give you extra constraints — and extra deductions — so an X-Sudoku often solves along paths a plain grid never would.

## Hyper Sudoku (Windoku)

Adds **four extra shaded 3x3 boxes** floating inside the grid, each of which must also hold 1–9 once. The overlapping regions create dense, satisfying chains of logic and a noticeably harder solve.

## Samurai Sudoku

Five 9x9 grids overlapping in a plus-sign shape, sharing corner boxes. You solve all five at once, using the shared boxes to carry deductions between them. It's a long, absorbing sit-down puzzle rather than a quick break.

## A puzzle that isn't Sudoku: Suko

**Suko** often shows up next to Sudoku in newspapers, so it's worth clearing up. Suko is a tiny 3x3 puzzle: place 1–9 once each so that four circled numbers equal the sums of the four cells around them, while colour-group totals match given targets. It borrows Sudoku's "each digit once" spirit but is a different puzzle with its own rules.

## Which should you try?

- **New to number puzzles?** Start with **mini** or [classic easy](/easy).
- **Want a twist without new math?** Try **jigsaw** or **X-Sudoku**.
- **Enjoy a bit of arithmetic?** **Killer** is the most rewarding step.
- **Craving a marathon?** **Samurai** will keep you busy for an hour.

Whichever branch you explore, they all reward the same calm, logical focus. Ready to warm up on the original? [Play a free classic puzzle](/) or try today's [daily Sudoku](/daily).