Mini vs Classic vs Killer vs Jigsaw vs Samurai Sudoku: Which Should You Play?

Mini Sudoku (6x6) — best for a quick break or learning the ropes

A 6x6 grid split into 2x3 boxes, filled with numbers 1–6. It uses the exact same core logic as full-size Sudoku, just with a third of the cells to track, so even our hardest Mini puzzles rarely take more than a few minutes. That makes it the easiest on-ramp if you're new to Sudoku — or if you're teaching a kid, since fewer numbers means less to memorize while the rules stay identical to every other variant on this page.

Basic scanning and naked singles get you through Easy and most Medium puzzles here. Hard mode is where naked pairs (covered in our solving techniques guide) start to matter, since a 6x6 grid runs out of "obvious" moves faster than a 9x9 one. The most common beginner mistake is skipping pencil marks because the grid looks small — do it anyway once you hit Hard, or you'll lose track of which numbers are actually still possible in a box. Play the daily puzzle or grind difficulty levels in Unlimited mode.

Classic Sudoku (9x9) — the standard everyone knows

The 9x9 grid with 3x3 boxes and digits 1–9 is the version printed in newspapers worldwide, and it's meaningfully harder than Mini Sudoku simply because there's three times the board to track. Easy and Medium puzzles are still mostly scanning and singles, but Hard puzzles reliably need naked pairs, pointing pairs, and careful pencil-mark discipline — the extra techniques in our solving techniques guide stop being optional and start being the only way through.

If you've mastered Mini Sudoku and want the "real" challenge, this is the natural next step: same rules, just enough extra rows, columns, and boxes to make guessing a bad strategy and systematic elimination the only reliable one. Every other variant on this page assumes you already know Classic, so it's worth spending real time here before branching out.

Sudoku X — Classic Sudoku plus two extra rules

Same 9x9 grid, same digits 1–9, but the two main diagonals must also contain 1–9 with no repeats. Those two extra lines sound minor, but they're genuinely useful: a diagonal constraint eliminates candidates that plain rows, columns, and boxes can't touch, so a well-placed diagonal check can crack a cell that looks stuck under Classic rules alone.

Because of that extra information, Sudoku X puzzles at a given difficulty often start with about as many clues as Classic — the challenge isn't fewer numbers, it's remembering to check two more lines on every move. The easiest way in is to physically trace both diagonals before you start scanning normally, so checking them becomes a habit rather than something you bolt on after getting stuck. Good pick if Classic Sudoku has started to feel routine and you want the same format with a sharper edge, without learning an entirely new rule set.

Killer Sudoku — Sudoku meets arithmetic

No starting clues at all. Instead, the grid is divided into "cages" — groups of cells outlined by a dashed border, each labeled with a target sum. The digits inside a cage must add up to that number and can't repeat, so you're solving two puzzles at once: the normal Sudoku placement logic, plus the arithmetic of which digit combinations can actually fit a cage of a given size and sum.

Small cages (two or three cells) are the best place to start, since a sum like 4 in a two-cell cage only has one possible combination (1+3). Hard puzzles lean on larger cages with several valid combinations, which is where cross-referencing a cage against its row, column, and box really pays off — pure arithmetic without that cross-check will leave you guessing. It rewards a different kind of thinking than the other variants and is a favorite for players who like Sudoku but want more math worked in.

Jigsaw Sudoku — when the boxes aren't boxes

The rows and columns still each need 1–9, but the nine 3x3 boxes are replaced with nine irregularly-shaped regions that tile the grid like puzzle pieces. Because the regions aren't neat squares, your usual "which box is this cell in" instincts don't apply — you have to actually trace the region's outline on every move, especially near where two regions interlock.

The core techniques are identical to Classic Sudoku — scanning, singles, pairs — so if you already know those, you already know how to solve Jigsaw. The difficulty is entirely spatial, not logical. New players usually lose the most time to misreading a region boundary near a corner; it's worth tracing the full outline of the two or three regions you're actively working before committing to a placement. It's disorienting at first and genuinely satisfying once it clicks.

Samurai Sudoku — five puzzles, one grid

Five overlapping 9x9 grids arranged in an X, sharing corner boxes with each other. It looks intimidating, but each of the five sub-grids follows normal Classic Sudoku rules — the challenge is that the shared corners must satisfy two grids' constraints simultaneously, and progress in one grid can unlock moves in another that looked stuck.

Because it's really five 9x9 puzzles, the total solve covers far more cells than any other variant here, even at the easiest difficulty — the individual logic never gets harder than Classic Sudoku, but there's a lot more of it. A solid approach is to work the four outer grids largely independently first, since each only shares one corner with the center, then use whatever's locked in those corners to crack the center grid last. Give yourself real time for this one; it's built for players who want a long, immersive session rather than a quick break — closer to a weekend project than a coffee break.

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